Vascularization of the Alouatta belzebul brain base / Vascularização da base do encéfalo de Alouatta belzebul

We studied the arterial circle in the brain of five specimens of the Alouatta belzebul primate. The material had the arterial system perfused (water at 40°C), injected with stained latex (Neoprene 650), fixed in aqueous formaldehyde solution (10%) and dissected for vessel verification. The arterial circle of this primate is composed of two vascular systems: the vertebra-basilar and the carotid ones, which anastomose to close the arterial circuit. In the caudal portion of the arterial circle, there are the vertebral arteries and their branches: the rostral spinal artery and the caudal inferior cerebellar artery. The anastomosis of the vertebral arteries gives rise to the basilar artery. It presented an anatomical variation at the beginning of its path, forming a double basilar artery, called arterial island. In its course, it emitted branches giving rise to the rostral inferior cerebellar artery, the pontine arteries, the rostral cerebellar arteries, the satellite rostral cerebellar arteries and its terminal branch, the caudal cerebral artery, which presented itself in two segments: the pre-communicating one and post-communicating, joining the internal carotid artery and originating the caudal communicating artery. This group of arteries and anastomoses enclose the caudal portion of the arterial circle. From the right and left internal carotid arteries begins the rostral portion of the arterial circle, which consists of the right and left rostral cerebral arteries and the right and left middle cerebral arteries. The rostral cerebral arteries anastomose into a single trunk, giving rise to the interhemispheric artery, and in A. belzebul and Sapajus libidinosus, the rostral communicating artery is absent. The interhemispheric artery goes to the midbrain region and the corpus callosum knee divides into pericalous artery and callosarginal artery, which will supply the pre and post-central regions of the cerebral hemispheres of this species, as well as other non-human and human primates. It is noted that in the first part of the left rostral cerebral artery, there is a direct inosculation between the recurrent branch of the rostral cerebral artery and left middle cerebral artery to supply the entorhinal region. This fact also occurs in Pongo spp. The middle cerebral artery travels along the lateral sulcus where it emits several superficial branches to irrigate the superior and inferior lateral cortical regions of the frontal, parietal and temporal lobes. It is not part of the arterial circle but is the terminal branch of the internal carotid artery. A. belzebul can be considered to depend on two sources of supply to the brain: the vertebra-basilar and carotid systems, contributing to the intervention of veterinarians during clinical and surgical procedures in other primates, as well as the preservation of wild animals.(AU)

Estudamos o círculo arterial no encéfalo de cinco espécimes do primata Alouatta belzebul. O material teve o sistema arterial perfundido (água a 40°C), injetado com látex corado (Neoprene 650), fixado em solução aquosa de formaldeído (10%) e dissecado para verificação dos vasos. O círculo arterial deste primata é composto por dois sistemas vasculares: vértebro-basilar e o sistema carotídeo, que se anastomosam para fechar o circuito arterial. Na porção caudal do círculo arterial encontra-se as artérias vertebrais e seus ramos: artéria espinal rostral e a cerebelar inferior caudal. A anastomose das artérias vertebrais dá origem a artéria basilar. Esta apresentou uma variação anatômica no início do seu trajeto, formando uma dupla artéria basilar, denominada ilha arterial. Em seu trajeto emitiu ramos dando origem a artéria cerebelar inferior rostral, as artérias pontinas, as artérias cerebelares rostrais, as artérias cerebelares rostrais satélites e o seu ramo terminal, a artéria cerebral caudal, que apresentou-se em dois segmentos: o pré-comunicante e pós-comunicante, unindo-se a artéria carótida interna e originando a artéria comunicante caudal. Este grupo de artérias e anastomoses encerram a porção caudal do círculo arterial. Das artérias carótidas internas direita e esquerda, inicia-se a porção rostral do círculo arterial, ao qual é constituído pelas artérias cerebrais rostrais direita e esquerda e as artérias cerebrais médias direita e esquerda. As artérias cerebrais rostrais se anastomosam em um tronco único dando origem a artéria inter-hemisférica e em A. belzebul e Sapajus libidinosus, a artéria comunicante rostral se encontra ausente. A artéria inter-hemisférica segue para região média do encéfalo e no joelho do corpo caloso se divide em artéria pericalosa e artéria calosomarginal, que vão suprir as regiões pré e pós-central dos hemisférios cerebrais desta espécie, assim como outros primatas não humanos e humano. Nota-se que na primeira parte da artéria cerebral rostral esquerda, ocorre uma inosculação direta entre o ramo recorrente da artéria cerebral rostral e artéria cerebral média esquerda para suprir a região entorrinal, esse fato também ocorre em Pongo spp. A artéria cerebral média segue seu trajeto pelo sulco lateral onde emite vários ramos superficiais para irrigar as regiões corticais supero e ínfero lateral do lobo frontal, parietal e temporal, esta não faz parte do círculo arterial mas é o ramo terminal da artéria carótida interna. Pode-se considerar que A. belzebul depende de duas fontes de suprimento para o encéfalo: os sistemas vértebro-basilar e carotídeo, contribuindo na intervenção de médicos veterinários durante os procedimentos clínicos e cirúrgicos em outros primatas, assim como na preservação de animais silvestres.(AU)

Vascularization of the Alouatta belzebul brain base / Vascularização da base do encéfalo de Alouatta belzebul

We studied the arterial circle in the brain of five specimens of the Alouatta belzebul primate. The material had the arterial system perfused (water at 40°C), injected with stained latex (Neoprene 650), fixed in aqueous formaldehyde solution (10%) and dissected for vessel verification. The arterial circle of this primate is composed of two vascular systems: the vertebra-basilar and the carotid ones, which anastomose to close the arterial circuit. In the caudal portion of the arterial circle, there are the vertebral arteries and their branches: the rostral spinal artery and the caudal inferior cerebellar artery. The anastomosis of the vertebral arteries gives rise to the basilar artery. It presented an anatomical variation at the beginning of its path, forming a double basilar artery, called arterial island. In its course, it emitted branches giving rise to the rostral inferior cerebellar artery, the pontine arteries, the rostral cerebellar arteries, the satellite rostral cerebellar arteries and its terminal branch, the caudal cerebral artery, which presented itself in two segments: the pre-communicating one and post-communicating, joining the internal carotid artery and originating the caudal communicating artery. This group of arteries and anastomoses enclose the caudal portion of the arterial circle. From the right and left internal carotid arteries begins the rostral portion of the arterial circle, which consists of the right and left rostral cerebral arteries and the right and left middle cerebral arteries. The rostral cerebral arteries anastomose into a single trunk, giving rise to the interhemispheric artery, and in A. belzebul and Sapajus libidinosus, the rostral communicating artery is absent...(AU)

Estudamos o círculo arterial no encéfalo de cinco espécimes do primata Alouatta belzebul. O material teve o sistema arterial perfundido (água a 40°C), injetado com látex corado (Neoprene 650), fixado em solução aquosa de formaldeído (10%) e dissecado para verificação dos vasos. O círculo arterial deste primata é composto por dois sistemas vasculares: vértebro-basilar e o sistema carotídeo, que se anastomosam para fechar o circuito arterial. Na porção caudal do círculo arterial encontra-se as artérias vertebrais e seus ramos: artéria espinal rostral e a cerebelar inferior caudal. A anastomose das artérias vertebrais dá origem a artéria basilar. Esta apresentou uma variação anatômica no início do seu trajeto, formando uma dupla artéria basilar, denominada ilha arterial. Em seu trajeto emitiu ramos dando origem a artéria cerebelar inferior rostral, as artérias pontinas, as artérias cerebelares rostrais, as artérias cerebelares rostrais satélites e o seu ramo terminal, a artéria cerebral caudal, que apresentou-se em dois segmentos: o pré-comunicante e pós-comunicante, unindo-se a artéria carótida interna e originando a artéria comunicante caudal. Este grupo de artérias e anastomoses encerram a porção caudal do círculo arterial. Das artérias carótidas internas direita e esquerda, inicia-se a porção rostral do círculo arterial, ao qual é constituído pelas artérias cerebrais rostrais direita e esquerda e as artérias cerebrais médias direita e esquerda. As artérias cerebrais rostrais se anastomosam em um tronco único dando origem a artéria inter-hemisférica e em A. belzebul e Sapajus libidinosus, a artéria comunicante rostral se encontra ausente. A artéria inter-hemisférica segue para região média do encéfalo e no joelho do corpo caloso se divide em artéria pericalosa e artéria calosomarginal, que vão suprir as regiões pré e pós-central dos hemisférios cerebrais desta espécie, assim como outros primatas não humanos e humano...(AU)

Gross anatomy and vascularization of the brain of pacarana (Dinomys branickii)

Background: The pacarana lives in South America and has herbivorous and nocturnal habits. It is a rare species with scarce data concerning its morphology and adding more data is important in establishing its vulnerability. The aim was to describe its macroscopic brain anatomy, as well as the brain vascularization.Materials, Methods & Results: Two specimens were available for this study, that were donated post-mortem. The animals were injected with latex and fixed with 10% formaldehyde. Upon exposure and removal of the brain its main features were described. The rhinal fissure is single and the lateral sulcus arises from its caudal part. There are two sagittal sulci, an extensive medial sulcus and a short lateral sulcus. The piriform lobe is vermiform and the rostral part is smaller. The caudal colliculus is larger than the rostral colliculus and they are separated by a sulcus. The cerebellum has oval shape and the flocculus lobe is not conspicuous. The cerebral arterial circle was analyzed and described. The brain is supplied by the vertebrobasilar system only. The cerebral arterial circle is formed by the terminal branch of the basilar artery, the caudal communicating artery, the rostral cerebral artery and the rostral communicating artery. The caudal and middle cerebellar arteries are branches of the basilar artery. The terminal branch of the basilar artery originates the rostral cerebellar artery and the caudal cerebral artery. From the end of the caudal communicating artery and the beginning of the rostral cerebral artery arises the middle cerebral artery.[...]

Gross anatomy and vascularization of the brain of pacarana (Dinomys branickii)

Background: The pacarana lives in South America and has herbivorous and nocturnal habits. It is a rare species with scarce data concerning its morphology and adding more data is important in establishing its vulnerability. The aim was to describe its macroscopic brain anatomy, as well as the brain vascularization.Materials, Methods & Results: Two specimens were available for this study, that were donated post-mortem. The animals were injected with latex and fixed with 10% formaldehyde. Upon exposure and removal of the brain its main features were described. The rhinal fissure is single and the lateral sulcus arises from its caudal part. There are two sagittal sulci, an extensive medial sulcus and a short lateral sulcus. The piriform lobe is vermiform and the rostral part is smaller. The caudal colliculus is larger than the rostral colliculus and they are separated by a sulcus. The cerebellum has oval shape and the flocculus lobe is not conspicuous. The cerebral arterial circle was analyzed and described. The brain is supplied by the vertebrobasilar system only. The cerebral arterial circle is formed by the terminal branch of the basilar artery, the caudal communicating artery, the rostral cerebral artery and the rostral communicating artery. The caudal and middle cerebellar arteries are branches of the basilar artery. The terminal branch of the basilar artery originates the rostral cerebellar artery and the caudal cerebral artery. From the end of the caudal communicating artery and the beginning of the rostral cerebral artery arises the middle cerebral artery.[...](AU)

Anatomia macroscópica e vascularização do encéfalo de emas (Rhea americana americana) / Macroscopic anatomy and brain vascularization in the greater rhea (Rhea americana americana)

Background: The Rhea americana americana is a wild bird belonging to the group of Ratites, and is important from the scientific point of view given their adaptability to captivity. Considering that information about its morphology is important for the viability of domesticating the species, the aim of this study was to macroscopically identify the brain regions, as well as the cerebral arteries and the cerebral arterial circuit in order to establish the cerebral vascular pattern and systematization.Materials, Methods & Results: Twenty one brains from young and adult Greater Rheas of both sexes were used from animals that had died due to natural causes and were then kept in a freezer. The specimens were thawed and incised in the cervical region to allow exposure of the left common carotid artery, which was cannulated. The vascular system was rinsed with 0.9% saline solution, then perfused with latex Neoprene 650 stained with red pigment. The animals were subsequently fixed in 3.7% aqueous formaldehyde solution for 72 h, and then they were dissected by removing the bones from the skull cap. The brains were analyzed, and the structures were identified, photographed, schematized and denominated. Morphometric measurements were performed on the basilar and cerebellar ventral caudal arteries, recording the values of length and width in millimeters with the aid of a digital caliper. The brain was divided into: telencephalon, diencephalon, brainstem and cerebellum; while externally, the observed structures are: olfactory bulbs, optical lobes, optic nerves, optic chiasm, pituitary and pineal glands. Vascularization was performed by the following arteries: ventral spinal artery, basilar artery, ventricular cerebellar arteries, medium ventricular cerebellar arteries, caudal branches of the carotid arteries of the brain, ventral mesencephalic artery, cerebral caudal arteries, rostral branches of the carotid arteries of the brain, middle cerebral arteries,[...]

Anatomia macroscópica e vascularização do encéfalo de emas (Rhea americana americana) / Macroscopic anatomy and brain vascularization in the greater rhea (Rhea americana americana)

Background: The Rhea americana americana is a wild bird belonging to the group of Ratites, and is important from the scientific point of view given their adaptability to captivity. Considering that information about its morphology is important for the viability of domesticating the species, the aim of this study was to macroscopically identify the brain regions, as well as the cerebral arteries and the cerebral arterial circuit in order to establish the cerebral vascular pattern and systematization.Materials, Methods & Results: Twenty one brains from young and adult Greater Rheas of both sexes were used from animals that had died due to natural causes and were then kept in a freezer. The specimens were thawed and incised in the cervical region to allow exposure of the left common carotid artery, which was cannulated. The vascular system was rinsed with 0.9% saline solution, then perfused with latex Neoprene 650 stained with red pigment. The animals were subsequently fixed in 3.7% aqueous formaldehyde solution for 72 h, and then they were dissected by removing the bones from the skull cap. The brains were analyzed, and the structures were identified, photographed, schematized and denominated. Morphometric measurements were performed on the basilar and cerebellar ventral caudal arteries, recording the values of length and width in millimeters with the aid of a digital caliper. The brain was divided into: telencephalon, diencephalon, brainstem and cerebellum; while externally, the observed structures are: olfactory bulbs, optical lobes, optic nerves, optic chiasm, pituitary and pineal glands. Vascularization was performed by the following arteries: ventral spinal artery, basilar artery, ventricular cerebellar arteries, medium ventricular cerebellar arteries, caudal branches of the carotid arteries of the brain, ventral mesencephalic artery, cerebral caudal arteries, rostral branches of the carotid arteries of the brain, middle cerebral arteries,[...](AU)

ESTUDO MACROSCÓPICO DO TELENCÉFALO, DA VASCULARIZAÇÃO DA BASE E SEIOS DA DURA-MÁTER EM Alouatta belzebul

Os primatas da espécie Alouatta belzebul, também conhecido como bugio, guariba e barbado são endêmicos do Brasil, de grande porte, movimentos lentos e locomoção quadrúpede. O conhecimento da morfologia desta espécie é escasso e, em alguns aspectos, como o encéfalo são inexistentes. O objetivo foi descrever a anatomia macroscópica do telencéfalo de Alouatta belzebul, assim como a vascularização da base do encéfalo, núcleos da base e os seios venosos da dura-máter. Estudaram-se 20 espécimes de Alouatta belzebul, onde os giros e sulcos encefálicos foram dissecados, os núcleos da base identificados e o sistema arterial e os seios venosos foram perfundidos com a injeção de látex corado. O telencéfalo do A. belzebul apresentou-se com características lisencefálicas, corroborando com várias outras espécies de primatas não humanos e diferindo de gêneros como Pan e Homo. Os núcleos da base estavam bastante evidentes e foram descritos o núcleo caudado, putâmen, globo pálido medial e globo pálido lateral, claustro e substância negra, que funcionalmente, estão relacionados com o comportamento motor da espécie. Na análise do índice de encefalização, observou-se que o Alouatta belzebul é filogeneticamente mais próximo de Sapajus e Macaca e mais distante de gêneros como Brachyteles e Callithrix, mostrando expressiva cognição e inteligência. Em relação à inclinação do sulco central, observou-se que em Alouatta belzebul a extremidade superior é posterior à extremidade inferior, dados que corroboram com o homem, babuínos e chimpanzés e revela um lobo frontal grande quando comparado Sapajus libidinosus, demonstrando o máximo de desenvolvimento cerebral nestes primatas. O círculo arterial do Alouatta belzebul é composto por dois sistemas vasculares: o vértebro-basilar e o sistema carotídeo, que se anastomosam para fechar o circuito arterial. Na porção caudal do círculo arterial encontram-se as artérias vertebrais e seus ramos: artéria espinal rostral e a cerebelar inferior caudal. A anastomose das artérias vertebrais dá origem à artéria basilar. Esta apresentou uma variação anatômica com a formação de uma dupla artéria basilar, denominada ilha arterial. Na dura-máter foram observados nove seios venosos: seio sagital dorsal, seio sagital ventral, seio transverso, seio reto, seio sigmoide, seio temporal, seio parietal, seio basilar e seio cavernoso, com semelhanças morfológicas na origem, trajeto e destino do fluxo sanguíneo para a veia jugular interna, auxiliando na função de drenagem venosa do encéfalo nesta espécie. Dos seios venosos observados, o seio cavernoso apresentou-se com uma importância clínica e cirúrgica considerável em Alouatta belzebul devido à sua disposição topográfica junto da artéria carótida interna e glândula hipófise, dados semelhantes aos descritos para Sapajus libidinosus, Macaca fascicularis, Macaca mulatta, Papio ursinus, Cercopithecus pygerithrus e Galago senegalensis. O estudo morfológico do telencéfalo, assim como os mecanismos de revestimento, irrigação arterial e drenagem dos seios venosos, gerou informações sobre a organização encefálica do primata Alouatta belzebul, que até então não haviam sido descritas e muitos desses dados geram subsídios para compreensão de outras áreas de investigações etológicas.

Primates of the species Alouatta belzebul, also known as howler monkeys, guariba and barbado are endemic to Brazil, of large size, slow movements and quadrupedal locomotion. The knowledge of the morphology of this species is scarce and, in some aspects, as the brain is non-existent. The objective was to describe the macroscopic anatomy of Alouatta belzebul's telencephalon, as well as the vascularization of the base of the brain, nuclei of the base and the venous sinuses of the dura mater. Twenty specimens of Alouatta belzebul were studied, where the brain gyres and grooves were dissected, the base nuclei were identified and the arterial system and venous sinuses were perfused with the injection of colored latex. The telencephalon of A. belzebul presented lysencephalic characteristics, corroborating with several other species of non-human primates and differing from genera such as Pan and Homo. The nuclei of the base were quite evident and the caudate nucleus, putamen, pale medial globe and pale lateral globe, cloister and black substance have been described, which are functionally related to the motor behavior of the species. In the analysis of the encephalization index, it was observed that the Alouatta belzebul is phylogenetically closer to Sapajus and Macaca and more distant from genera such as Brachyteles and Callithrix, showing expressive cognition and intelligence. Regarding the inclination of the central groove, it was observed that in Alouatta belzebul the upper extremity is posterior to the lower extremity, data that corroborate with man, baboons and chimpanzees and reveal a large frontal lobe when compared to Sapajus libidinosus, showing the maximum development in these primates. The arterial circle of the Alouatta belzebul consists of two vascular systems: the vertebro-basilar and the carotid system, which anastomose to close the arterial circuit. In the caudal portion of the arterial circle are the vertebral arteries and their branches: the rostral spinal artery and the caudal inferior cerebellar artery. Anastomosis of the vertebral arteries gives rise to the basilar artery. This presented an anatomical variation with the formation of a double basilar artery, called the arterial island. Nine venous sinuses were observed in the dura mater: dorsal sagittal sinus, ventral sagittal sinus, transverse sinus, straight sinus, sigmoid sinus, temporal sinus, parietal sinus, basilar sinus and cavernous sinus, with morphological similarities in the origin, path and destination of the flow blood to the internal jugular vein, helping in the venous drainage function of the brain in this species. Of the venous sinuses observed, the cavernous sinus was of considerable clinical and surgical importance in Alouatta belzebul due to its topographic arrangement next to the internal carotid artery and pituitary gland, data similar to those described for Sapajus libidinosus, Macaca fascicularis, Macaca mulatta, Papio ursinus, Cercopithecus pygerithrus and Galago senegalensis. The morphological study of the telencephalon, as well as the mechanisms of lining, arterial irrigation and drainage of the venous sinuses, generated information about the brain organization of the primate Alouatta belzebul, which had not been previously described and many of these data generate subsidies for understanding other áreas ethological investigations.

Evaluation of the isoflurane-sparing effects of a constant rate infusion of remifentanil undergoing mastectomy in dogs / Avaliação da concentração expirada de isoflurano em infusão continua de remifentanil em cadelas submetidas a mastectomia

Os objetivos deste estudo são a avaliação dos efeitos de duas taxas fixas de infusão continua de remifentanil na concentração expirada de isoflurano (ETiso) em cadelas submetidas à mastectomia. Foram utilizadas 18 cadelas, 12+2 anos de idade e pesando 15+5 Kg. Os animais foram distribuídos aleatoriamente em 3 grupos (n=6/grupo) e submetidos à mastectomia unilateral devido a neoplasia mamária. Todos os animais foram pré-medicados com morfina (0,5 mg Kg-1) e acepromazina (0,03 mg Kg-1), ambas por via intramuscular (IM). A indução da anestesia foi realizada com propofol (dose-efeito). Os animais foram intubados e conectados a um sistema circular com reinalação de gases. Foi utilizada ventilação com pressão positiva intermitente para manutenção de normocapnia com fluxo de oxigênio de 2 L/min e FiO2 de 100%. A anestesia foi mantida com isoflurano e solução salina (grupo controle [GCON], n=6) ou infusão intravenosa de remifentanil na taxa de 0,15 ?g Kg-1min-1 (REMI 0,15 n=6) ou 0,3 ?g Kg-1min-1 (REMI 0,3 n=6). As variáveis cardiovasculares e a ETiso foram monitoradas antes e a cada 15 minutos após o início da cirurgia. Os dados foram analisados por ANOVA com repetições múltiplas para comparações entre momentos e ANOVA seguida de teste Student Newman Keuls (p£0.05) para comparações entre grupos. A frequência cardíaca foi menor em todos os momentos nos grupos REMI 0,15 e REMI 0,3 em comparação com GCON, sendo que não foram encontradas diferenças estatísticas para essa variável entre os dois grupos com infusão de remifentanil. Adicionalmente, os valores de pressão arterial (PAS, PAM e PAD) não apresentaram diferenças entre grupos. Os valores basais (antes da cirurgia) de ETiso não apresentaram diferenças entre os 3 grupos. Após o início da cirurgia, a ETiso variou entre 1,37±0,3 e 1,05±0,19 no grupo controle; nos grupos REMI 0,15 e REMI 0,3 a ETiso foi 36,5% e 65,7% menor que no grupo controle (M15).[...](AU)

The aims of this study were to evaluate the effects of two constant rate infusions of remifentanil on end tidal isoflurane (ETiso) in dogs undergoing mastectomy surgery. Eighteen bitches, 12+2 years of age, weighing 15+5 Kg were randomized into 3 groups (n=6/group) and underwent unilateral mastectomy due to mammary neoplasia. All animals received the premedications of morphine (0.5 mg Kg-1) and acepromazine (0.03 mg Kg-1) by intramuscular route (IM). Propofol dose-effect was used for induction of anesthesia. The animals were intubated and connected to a circle breathing system, and IPPV (intermittent positive pressure ventilation) was used to maintain normocapnia with an oxygen flow rate of 2 L/min and FiO2 100%. Anesthesia was maintained with isoflurane and saline solution (control group [GCON], n=6) or intravenous infusion of remifentanil at a rate of 0.15 ?g Kg-1min-1 (REMI 0.15 n=6) or 0.3 ?g Kg-1min-1 (REMI 0.3 n=6). Cardiopulmonary variables and ETiso were monitored before and every 15 minutes after the start of surgery. The data were analyzed by ANOVA with multiple repetitions between moments and ANOVA followed by the Student Newman Keuls test (p£0.05) for comparisons between groups. Heart rate was lower at all moments in the REMI 0.15 and REMI 0.3 groups than in the GCON, and heart rate was not significantly different between the two remifentanil infusion groups. Additionally, the arterial blood pressure values (SAP, MAP and DAP) were not different between all groups. Baseline values (before surgery) of ETiso were not different between the 3 groups. After the start of surgery, ETiso ranged from 1.37±0.3 to 1.05±0.19 in the control group; in the REMI 0.15 and REMI 0.3 groups, ETiso was 36.5% and 65.7% lower than in the control group (M15). Remifentanil infusion reduced ETiso in a dose-dependent manner in animals undergoing radical mastectomy without causing significant cardiopulmonary alterations.(AU)

A systematic study of the brain base arteries in the rabbit (Oryctolagus cuniculus) / Sistematização das artérias da base do encéfalo e suas fontes de suprimento sanguíneo em coelho da raça Nova Zelândia (Oryctolagus cuniculus)

The brains of 30 New Zealand rabbits (Oryctolagus cuniculus) were injected with red stained latex. The arteries of the ventral surface of the brain were systematized on the right (R) and on the left (L) side with the respective percentage of appearance: the aortic arch emitted the braquicephalic trunk and the left subclavian artery (83.3%); or the braquicephalic trunk, the left common carotid artery and the left subclavian artery (16.7%). The braquicephalic trunk emitted the right and the left common carotid arteries and the right subclavian artery (83.3%); or the right common carotid artery and the right subclavian artery (16.7%). The common carotid arteries were divided into external and internal carotid arteries (96.7% on the R, 100% on the L.). The internal carotid artery to the R was present (96.7%) and absent (3.3%), and to the L, was present (100%). The rostral choroidal artery to the R was collateral branch of the rostral branch of the internal carotid artery (83.3%), collateral branch of caudal branch of the internal carotid artery (16.7%), and to the L was collateral branch of the rostral branch of the internal carotid artery (93.3%), collateral branch of the caudal branch of the internal carotid artery (6.7%). The middle cerebral artery to the R and to the L was single (80%) and double (20%). The rostral cerebral artery to the R had middle caliber (90%), thin caliber (6.7%) and too thin caliber (3.3%), and to the L had middle caliber (76.7%), thin caliber (16.7%) and too thin caliber (6.7%). The internal ethmoidal artery was absent (73.3%), present and single (26.7%). The caudal cerebral artery to the R was single (66.7%), double (26.7%) and triple (6.7%), and to the L was single (63.3%) and double (36.7%). The terminal branches of the right and left vertebral arteries were present (100%, and formed the basilar artery (100%). The ventral spinal artery was present (100%). The caudal cerebellar artery, to the R was single (43.3%), single with labyrinthic artery isolated (26.7%) and double (30%), and to the L was single (50%), single with labyrinthic artery isolated (6.7%), double (40%) and triple (3.3%). The trigeminal artery to the R and to the L was present (100%). The rostral cerebellar artery to the R was single (53.3%) and double (46,7%), and to the L was single (63.3%) and double (36.7%). The rabbit's cerebral arterial circle was caudally closed (100%) and rostrally closed (93.3%) or opened (6.7%). The brain was supplied by the vertebral-basilar and carotid systems.(AU)

Foram utilizados 30 encéfalos de coelhos Nova Zelândia (Oryctolagus cuniculus), injetados com látex, corado em vermelho, com objetivo de sistematizar as artérias da base do encéfalo e suas fontes de suprimento sanguíneo. Sistematizou-se a origem das fontes de suprimento sanguíneo para o encéfalo e as artérias (Aa) da face ventral do mesmo, tanto à direita (D) como à esquerda (E), com suas respectivas percentagens de aparecimento: o arco aórtico emitiu tronco braquiocefálico e artéria (A.) subclávia E (83,3%), ou tronco braquiocefálico, A. carótida comum E e A. subclávia E (16,7%). O tronco braquiocefálico lançou A. carótida comum D e E e A. subclávia D (83,3%), ou A. carótida comum D e A. subclávia D (16,7%). A. carótida comum dividiu-se em Aa carótidas externa e interna (96,7% D, 100% E). A. carótida interna D presente (96,7%) e ausente (3,3%), à E presente (100%). A. corióidea rostral D ramo colateral do ramo rostral da A. carótida interna D (83,3%), ramo colateral do ramo caudal da A. carótida interna D (16,7%), à E, ramo colateral do ramo rostral da A. carótida interna E (93,3%), ramo colateral do ramo caudal da A. carótida interna E (6,7%). A. cerebral média D e E ímpar (80%) e dupla (20%). A. cerebral rostral D com calibre médio (90%), calibre fino (6,7%), calibre muito fino (3,3%), à E, com calibre médio (76,7%), calibre fino (16,7%), calibre muito fino (6,7%). A. etmoidal interna ausente (73,3%), presente e ímpar (26,7%). A. cerebral caudal D, ímpar (66,7%), dupla (26,7%) e tripla (6,7%), à E, ímpar (63,3%) e dupla (36,7%). Ramos terminais --das Aa. vertebrais D e E presentes (100%) formaram a A. basilar (100%). A. espinhal ventral ímpar presente (100%). A. cerebelar caudal D, ímpar (43,3%), ímpar com A. labiríntica isolada (26,7%) e dupla (30%), à E, ímpar (50%), ímpar com A. labiríntica isolada (6,7%), dupla (40%) e tripla (3,3%). A. trigeminal D e E presente (100%). A. cerebelar rostral D, ímpar (53,3%) e dupla (46,7%), à E, ímpar (63,3%) e dupla (36,7%). Observou-se que o círculo arterial Cerebral do coelho foi fechado caudalmente (100%), rostralmente fechado (93,3%) e aberto (6,7%). O encéfalo foi suprido pelos sistemas vértebro-basilar e carotídeo.(AU)

SISTEMATIZAÇÃO, DISTRIBUIÇÃO E TERRITÓRIOS DAS ARTÉRIAS CEREBRAIS ROSTRAL, MÉDIA E CAUDAL NA SUPERFÍCIE DO ENCÉFALO EM NUTRIA (Myocastor coypus)

Foram utilizados 30 encéfalos de nutria (Myocastor coypus), injetados com látex, corado em vermelho, com objetivo de sistematizar e descrever a distribuição e territórios das artérias cerebrais rostral, média e caudal e suas ramificações na superfície dos hemisférios cerebrais e no tronco encefálico. A artéria carótida interna apresentouse atrofiada, sendo o encéfalo vascularizado exclusivamente pelo sistema vértebrobasilar. A artéria vertebral penetrou pelo forame magno, e seus antímeros anastomosaram-se formando uma calibrosa artéria basilar. A artéria basilar, de grande calibre, alcançou o sulco rostral da ponte, dividiu-se em dois ramos terminais, em uma divergência de aproximadamente 90°, e lançou as artérias cerebelar rostral, cerebral caudal, hipofisária, corióidea rostral e ramos centrais para o lobo piriforme. Após, os ramos terminais da artéria basilar projetaram-se rostro-lateralmente até a altura da origem aparente do nervo oculomotor (III par craniano), e curvaram-se alcançando o trato óptico, lançando a artéria cerebral média e a artéria cerebral rostral, seu ramo terminal. A artéria cerebelar rostralemitiu um ramo tectal mesencefálico caudal, para a face caudal do colículo caudal. A artéria cerebral caudal, normalmente única, de grosso calibre, projetava-se látero-dorsalmente para o interior da fissura transversa do cérebro, lançando as artérias tectal mesencefálica rostral (componente proximal) e interhemisférica caudal. A artéria tectal mesencefálica rostral vascularizou a maior parte do tecto mesencefálico, e os ramos terminais das artérias tectais mesencefálicas, rostral e caudal, formaram uma rede anastomótica sobre a superfície dos colículos rostrais e caudais. A artéria inter-hemisférica caudal lançou ramos centrais, artérias corióidea caudal (esta anastomosava-se com a artéria corióidea rostral, vascularizando o diencéfalo e o hipocampo), hemisféricas occipitais (para o pólo occipital do hemisfério cerebral), ramos tectais mesencefálicos rostrais (componentes distais), e então contornava o esplênio do corpo caloso anastomosando-se em ósculo com a artéria inter-hemisférica rostral. A artéria cerebral média, de grande calibre, projetava-se pelo interior da fossa lateral do cérebro, lançando ramos centrais caudais e rostrais para o páleo-palio da região. Ela ultrapassou o sulco rinal lateral, formando um a dois eixos principais para a face convexa do hemisfério cerebral, originando ramos hemisféricos convexos caudais e rostrais, e suas ramificações terminais anastomosavam-se em ósculo no lobo parietal com os ramos das artérias hemisféricas mediais rostrais, ramo da artéria cerebral rostral. A artéria cerebral rostral, de grosso calibre, projetou-se rostro-medialmente, na altura do quiasma óptico, emitindo um ramo medial, para a fissura longitudinal do cérebro. Seu eixo principal projetava-se rostralmente, acompanhando a fissura longitudinal do cérebro, até o bulbo olfatório, continuando-se para a cavidade nasal como artéria etmoidal interna. Esta emitiu ramos centrais, hemisférico medial e artérias lateral e medial do bulbo olfatório. O ramo medial anastomosava-se com seu homólogo contralateral, quando presente, fechando o círculo arterial cerebral rostralmente, formando uma artéria comunicante rostral, mediana ímpar. Esta se bifurcou nas artérias inter-hemisféricas rostrais, que vascularizavam toda face medial dos hemisférios cerebrais, até o esplênio do corpo caloso, emitindo as artérias hemisférica rostral e hemisférica medial rostral, sendo que os ramos terminais desta alcançavam a face convexa, anastomosando-se com os ramos terminais da artéria cerebral média.

Thirty nutria brains were used (Myocastor coypus), injected with latex and stained in red, in order to systematize and describe the distribution and the territories of the rostral, middle and caudal cerebral arteries and their ramifications in the surface of cerebral hemispheres and in the brain stem in nutria. The internal carotid artery was atrophied, being the encephalic vascularized exclusively by the vertebro-basilar system. The vertebral artery penetrated the magnum foramen, and their antimeres anastomosed to form a calibrous basilar artery. The basilar artery, of great caliber, reached the rostral sulcus of the pons, divided into two terminal branches, at a divergence of approximately 90°, and launched the rostral cerebellar, caudal cerebral, hypophyseal, rostral choroid arteries and central branches to the piriform lobe. Afterwards, the terminal branches of the basilar artery were projected rostrolaterally up to the apparent origin of the oculomotor nerve (III cranial nerve), and bent over reaching the optic tract, launching the middle cerebral artery and the rostral cerebral artery, its terminal branch. The rostral cerebellar artery emitted a caudal tectal mesencephalic branch, to the caudal surface of the caudal colliculus. The caudal cerebral artery, usually unique, of large caliber, projected laterally into the transverse fissure of the brain, launching the rostral tectal mesencephalic (proximal component) and caudal inter-hemispheric arteries. The rostral tectal mesencephalic artery vascularized most of the mesencephalic roof, and the terminal branches of the tectal mesencephalic arteries, rostral and caudal, formed an anastomotic network on the surface of rostral and caudal colliculus. The caudal inter-hemispheric artery emitted central branches, caudal choroid (this anastomosis with the rostral choroidal artery, vascularizing of the diencephalon and hippocampus), occipital hemispheres artery (to the occipital pole of the cerebral hemisphere), rostrais tectral mesencephalic branches (distal components), and then bypassed the splenius of the corpus callosum anastomosing "in osculum" with the rostral inter-hemispheric artery. The medium cerebral artery, of great caliber, projected through the interior of the cerebral lateral fossa, Releasing caudal and rostrais central branches to the paleopallio region. It crossed the lateral rinal groove, forming one to two main axes to the convex surface of the cerebral hemisphere, originating caudal and rostral convex hemispheric branches, and its terminal branches anastomosed "in osculum" in the parietal lobe with the branches of the mediais rostrais hemispherics arteries, branch of the rostral cerebral artery. The rostral cerebral artery, of large caliber, projected rostro-medially, at the level of optic chiasm, emitting a medial branch, for the cerebral longitudinal fissure. Its main axis was projected rostrally, accompanying the cerebral longitudinal fissure, until the olfactory bulb, continuing to the nasal cavity as internal ethmoidal artery. It emitted central branches, medial hemispheric and lateral and medial of the olfactory bulb arteries. The medial branch was anastomosed with its contralateral homologous, when present, closing the cerebral arterial circle rostrally, forming a rostral communicating artery, unique median. This bifurcated in the inter-hemispheric rostrais arteries, which vascularized the entire medial face of the cerebral hemispheres, until the splenius of the corpus callosum, emitting the rostral hemispherical and hemispherical medial rostral arteries, being that the terminal branches of this reached the convex surface, anastomosing with the terminal branches of the middle cerebral artery.

Systematization, description and territory of the caudal cerebral artery of the brain in broad-snouted Caiman (Caiman latirostris) / Sistematização, descrição e território da artéria cerebral caudal no cérebro do jacaré do papo-amarelo (Caiman latirostris)

Thirty heads with the neck segment of Caiman latirostris were used. The animals were provided from a creation center called Mister Caiman, under the authorization of the Brazilian Institute of Environment and Renewable Natural Resources (Ibama). Animals were sacrificed according to the slaughtering routine of the abattoir, and the heads were sectioned at the level of the third cervical vertebra. The arterial system was washed with cold saline solution, with drainage through jugular veins. Subsequently, the system was filled with red colored latex injection. Pieces were than fixed in 20 percent formaldehyde, for seven days. The brains were removed, with a spinal cord segment, the duramater removed and the arteries dissected. At the level of the hypophysis, the internal carotid artery gave off a rostral branch, and a short caudal branch, continuing, naturally, as the caudal cerebral artery. This artery projected laterodorsalwards and, as it overpassed the optic tract, gave off its I (the first) central branch. Penetrated in the cerebral transverse fissure, emitting the diencephalic artery and next its II (second) central branch. Still inside the fissure, originated occipital hemispheric branches and a pineal branch. Emerged from the cerebral transverse fissure, over the occipital pole of the cerebral hemisphere. Projected rostralwards, sagital to the cerebral longitudinal fissure, as interhemispheric artery. This artery gave off medial and convex hemispheric branches to the respective surfaces of the cerebral hemispheres, anastomosed with its contralateral homologous, forming the common ethmoidal artery. This artery entered the fissure between the olfactory peduncles, emerging ventrally and dividing into ethmoidal arteries, right and left, which progressed towards the nasal cavities, vascularizing them. The territory of the caudal cerebral artery included the most caudal area of the base of the cerebral hemisphere, its convex surface, the olfactory peduncles and bulbs, the choroid plexuses and the diencephalus with its parietal organs.

Foram utilizadas trinta cabeças com o segmento de pescoço de Caiman latirostris. Os animais eram provenientes do Criatório Mister Caiman sob a autorização do Instituto Brasileiro de Meio Ambiente e dos Recursos Naturais Renováveis (Ibama). Os animais foram sacrificados de acordo com as normas de rotina de abate do frigorífico e as cabeças foram seccionadas na altura da terceira vértebra cervical. O sistema arterial foi lavado com solução salina 0.9 por cento resfriada, com drenagem pelas veias jugulares. Em seguida, o sistema foi preenchido com injeção de látex, corado em vermelho As peças foram então fixadas em formaldeído a 20.0 por cento por sete dias. O cérebro foi removido, com um segmento de medula espinhal, a dura-máter retirada e as artérias dissecadas. Na altura da hipófise, a artéria carótida interna emitiu um ramo rostral e, um curto ramo caudal, continuando-se naturalmente, como artéria cerebral caudal. Esta se projetou látero-dorsalmente e ao sobrepassar o trato óptico, emitiu seu I (primeiro) ramo central. Penetrou na fissura transversa do cérebro, lançando a artéria diencefálica e a seguir seu II (segundo) ramo central. Ainda dentro da fissura originou ramos hemisféricos occipitais, e um ramo pineal. Emergiu da fissura transversa do cérebro, no pólo occipital do hemisfério cerebral. Projetou-se rostralmente, sagital a fissura longitudinal do cérebro, como artéria interhemisférica. Esta artéria lançou ramos hemisféricos convexos e mediais para as respectivas faces dos hemisférios cerebrais, anastomosou-se com sua homóloga contralateral, formando uma artéria etmoidal comum. Esta mergulhou na fissura entre os pedúnculos olfatórios emergindo ventralmente e, dividindo-se em artérias etmoidais, direita e esquerda, as quais progrediram para as cavidades nasais, vascularizando-as. O território da artéria cerebral caudal compreendeu a área mais caudal da base do hemisfério cerebral, sua face convexa, os pendúculos e bulbos olfatórios, plexo corióides e o diencéfalo com seus órgãos parietais.

Systematization, description and territory of the caudal cerebral artery of the brain in broad-snouted Caiman (Caiman latirostris) / Sistematização, descrição e território da artéria cerebral caudal no cérebro do jacaré do papo-amarelo (Caiman latirostris)

Thirty heads with the neck segment of Caiman latirostris were used. The animals were provided from a creation center called Mister Caiman, under the authorization of the Brazilian Institute of Environment and Renewable Natural Resources (Ibama). Animals were sacrificed according to the slaughtering routine of the abattoir, and the heads were sectioned at the level of the third cervical vertebra. The arterial system was washed with cold saline solution, with drainage through jugular veins. Subsequently, the system was filled with red colored latex injection. Pieces were than fixed in 20 percent formaldehyde, for seven days. The brains were removed, with a spinal cord segment, the duramater removed and the arteries dissected. At the level of the hypophysis, the internal carotid artery gave off a rostral branch, and a short caudal branch, continuing, naturally, as the caudal cerebral artery. This artery projected laterodorsalwards and, as it overpassed the optic tract, gave off its I (the first) central branch. Penetrated in the cerebral transverse fissure, emitting the diencephalic artery and next its II (second) central branch. Still inside the fissure, originated occipital hemispheric branches and a pineal branch. Emerged from the cerebral transverse fissure, over the occipital pole of the cerebral hemisphere. Projected rostralwards, sagital to the cerebral longitudinal fissure, as interhemispheric artery. This artery gave off medial and convex hemispheric branches to the respective surfaces of the cerebral hemispheres, anastomosed with its contralateral homologous, forming the common ethmoidal artery. This artery entered the fissure between the olfactory peduncles, emerging ventrally and dividing into ethmoidal arteries, right and left, which progressed towards the nasal cavities, vascularizing them. The territory of the caudal cerebral artery included the most caudal area of the base of the cerebral hemisphere, its convex surface, the olfactory peduncles and bulbs, the choroid plexuses and the diencephalus with its parietal organs.(AU)

Foram utilizadas trinta cabeças com o segmento de pescoço de Caiman latirostris. Os animais eram provenientes do Criatório Mister Caiman sob a autorização do Instituto Brasileiro de Meio Ambiente e dos Recursos Naturais Renováveis (Ibama). Os animais foram sacrificados de acordo com as normas de rotina de abate do frigorífico e as cabeças foram seccionadas na altura da terceira vértebra cervical. O sistema arterial foi lavado com solução salina 0.9 por cento resfriada, com drenagem pelas veias jugulares. Em seguida, o sistema foi preenchido com injeção de látex, corado em vermelho As peças foram então fixadas em formaldeído a 20.0 por cento por sete dias. O cérebro foi removido, com um segmento de medula espinhal, a dura-máter retirada e as artérias dissecadas. Na altura da hipófise, a artéria carótida interna emitiu um ramo rostral e, um curto ramo caudal, continuando-se naturalmente, como artéria cerebral caudal. Esta se projetou látero-dorsalmente e ao sobrepassar o trato óptico, emitiu seu I (primeiro) ramo central. Penetrou na fissura transversa do cérebro, lançando a artéria diencefálica e a seguir seu II (segundo) ramo central. Ainda dentro da fissura originou ramos hemisféricos occipitais, e um ramo pineal. Emergiu da fissura transversa do cérebro, no pólo occipital do hemisfério cerebral. Projetou-se rostralmente, sagital a fissura longitudinal do cérebro, como artéria interhemisférica. Esta artéria lançou ramos hemisféricos convexos e mediais para as respectivas faces dos hemisférios cerebrais, anastomosou-se com sua homóloga contralateral, formando uma artéria etmoidal comum. Esta mergulhou na fissura entre os pedúnculos olfatórios emergindo ventralmente e, dividindo-se em artérias etmoidais, direita e esquerda, as quais progrediram para as cavidades nasais, vascularizando-as. O território da artéria cerebral caudal compreendeu a área mais caudal da base do hemisfério cerebral, sua face convexa, os pendúculos e bulbos olfatórios, plexo corióides e o diencéfalo com seus órgãos parietais.(AU)

A systematic study of the brain base arteries in the turkey (Meleagris gallopavo) / Sistematização das artérias na base do encéfalo e suas fontes de suprimento sanguíneo em peru (Meleagris gallopavo)

Thirty heads with neck segments of turkeys (Meleagris gallopavo) were dissected for a systematic study of the arteries. The frequency of the arteries found was: Cerebral carotid artery, intercarotid anastomosis and internal ophthalmic artery (100 percent). Caudal branch of the cerebral carotid artery to the right (R) vestigial artery (70 percent) and developed (30 percent) and to the left (L) developed (70 percent) and vestigial artery (30 percent). Ventral tectal mesencephalic artery in (70 percent) to R and (30 percent) to L was the direct branch of the cerebral carotid artery to L (70 percent) and to R (30 percent) collateral branch of the developed caudal branch. Basilar artery to L in (70 percent) and to R (30 percent) formed from the developed caudal branch; rostral ventral cerebellar artery present (86.7 percent) and absent (13.3 percent) to R and L. Caudal ventral cerebellar artery to R single (73.3 percent), double (23.3 percent) and triple (3.3 percent); caudal ventral cerebellar artery to L single (73.3 percent) and double (26.7 percent). Dorsal spinal artery branch of caudal ventral cerebellar artery to R (80 percent) and to L (73.3 percent). The rostral branch of cerebral carotid artery showed as collateral branches the single caudal cerebral artery to R (100 percent) and to L (96.7 percent) while in (3.3 percent) it was double. The middle cerebral artery was single to R and L (100 percent). Cerebroethmoidal artery to R and L (100 percent) with its collateral branch to single rostral cerebral artery (90 percent) to R and (86.7 percent) to L and double (10 percent) to R and (13.3 percent) to L. Ethmoidal artery to R and to L (100 percent) single. The cerebral arterial circle was rostrally and caudally opened, so that the cerebral blood supply was exclusively made by the carotid system.(AU)

Trinta cabeças de peru (Meleagris gallopavo), com segmento de pescoço, foram dissecados para o estudo sistemático das artérias. As maiores ocorrências das artérias foram: Artéria (A.) carótida do cérebro, anastomose intercarótica e A. oftálmica interna (100 por cento). Ramo caudal da carótida do cérebro à direita (D) vestigial (70 por cento) e desenvolvido (30 por cento) e à esquerda (E) desenvolvido (70 por cento) e vestigial (30 por cento). A A. tectal mesencefálica ventral em (70 por cento) à D e (30 por cento) à E foi ramo direto da A. carótida do cérebro à E (70 por cento) e à D (30 por cento) ramo colateral do ramo caudal desenvolvido. A A. basilar à E em (70 por cento) e à D (30 por cento) formou- se do ramo caudal desenvolvido. A. cerebelar ventral rostral presente (86,7 por cento) e ausente (13,3 por cento) à D e E. A. cerebelar ventral caudal à D única (73,3 por cento), dupla (23,3 por cento) e tripla (3,3 por cento). A. cerebelar ventral caudal à E única (73,3 por cento) e dupla (26,7 por cento). A. espinhal dorsal ramo da A. cerebelar ventral caudal à D (80 por cento) e à E (73,3 por cento). O ramo rostral da A. carótida do cérebro apresentou como ramos colaterais a A. cerebral caudal à D única (100 por cento) e à E (96,7 por cento) já em (3,3 por cento) era dupla; A. cerebral média única à D e E (100 por cento). A. cerebroetmoidal à D e E (100 por cento) com seu ramo colateral a A. cerebral rostral única (90 por cento) à D e (86,7 por cento) à E e dupla (10 por cento) à D e (13,3 por cento) à E. A. etmoidal à D e à E (100 por cento) única. Observou-se que o círculo arterial cerebral foi aberto rostralmente e caudalmente e o suprimento de sangue para o encéfalo foi exclusivamente pelo sistema carotídeo.(AU)

SISTEMATIZAÇÃO DAS ARTÉRIAS DA BASE DO ENCÉFALO, DISTRIBUIÇÃO E TERRITÓRIOS DAS ARTÉRIAS CEREBRAIS ROSTRAL, MÉDIA E CAUDAL E DA ARTÉRIA MESENCEFÁLICA NA SUPERFÍCIE DO ENCÉFALO EM TARTARUGA (Trachemys scripta elegans)

Foram utilizados 30 encéfalos de tartaruga (Trachemys scripta elegans), injetados com látex, corado em vermelho, com objetivo de sistematizar e descrever a distribuição e territórios das artérias carótidas internas e suas principais ramificações na superfície do encéfalo. As artérias carótidas internas apresentaram uma anastomose intercarótica e a artéria oftálmica interna. No terço médio rostral da hipófise, a artéria carótida interna bifurcou-se em seus dois ramos terminais, rostral e caudal. O ramo rostral lançou a artéria corióidea rostral, a artéria orbitária e uma sequência de artérias cerebrais médias. O ramo rostral, após originar a última artéria cerebral média, continuou-se como artéria cerebral rostral, e ao alcançar a fissura longitudinal do cérebro, apresentou uma anastomose com sua homóloga contralateral, originando a artéria comunicante rostral, fazendo o primeiro fechamento rostral do círculo arterial cerebral, quando presente. Logo a seguir, a continuação das artérias cerebrais rostrais anastomosaram-se formando uma artéria inter-hemisférica rostral, fechando por uma segunda vez o círculo arterial cerebral, rostralmente. A artéria inter-hemisférica rostral, dividiu-se em artérias hemisféricas mediais rostrais direita e esquerda; cada uma lançou um ramo mais ventral que se projetava rostralmente, ligando-se ventralmente ao anel vascular. A artéria hemisférica medial rostral ramificava-se caudalmente e dorsalmente, ascendendo à face convexa do hemisfério cerebral, no pólo rostral deste. O eixo principal da artéria hemisférica medial rostral, normalmente recebia a anastomose do ramo profundo da artéria inter-hemisférica caudal. Suas terminações dorsais, na face convexa, anastomosavam-se em osculum com as terminações da última artéria hemisférica medial caudal e com as terminações do ramo terminal dorsal da rede da artéria cerebral média. A artéria carótida interna ao projetar-se dorsalmente na altura do tuber cinéreo, após emitir seu ramo rostral, continuou-se caudalmente como seu ramo caudal. O ramo caudal ao projetar-se caudalmente na face ventral do corpo mesencefálico, medialmente ao lobo piriforme, lançou seu primeiro ramo colateral, a artéria cerebral caudal. A artéria cerebral caudal lançou ramos hemisféricos occipitais, ramo corióideo caudal (diencefálica) e ramos pineais, continuando-se para o interior da fissura longitudinal do cérebro como artéria inter-hemisférica caudal. A artéria inter-hemisférica caudal projetou-se rostralmente, geralmente pelo interior da fissura longitudinal do cérebro, emitindo ramos hemisféricos mediais que ascendiam para a face convexa do hemisfério cerebral. O ramo profundo da artéria inter-hemisférica caudal projetou-se profundamente na fissura longitudinal do cérebro no sentido rostral, indo anastomosar-se com a artéria hemisférica medial rostral ramo da artéria inter-hemisférica rostral. Após lançar a artéria cerebral caudal, o ramo caudal da artéria carótida interna contornou lateralmente a origem aparente do III par de nervos cranianos, oculomotor, emitiu caudolateralmente seu principal ramo colateral, a artéria mesencefálica, continuando-se caudomedialmente com um calibre bem mais fino, anastomosando-se com seu homólogo contralateral, originando a artéria basilar. A porção de fino calibre emitiu ainda seu último ramo colateral, a artéria trigeminal. A anastomose dos ramos caudais fechou o círculo arterial cerebral caudalmente. A artéria basilar lançou ramos medulares e as artérias espinhais dorsais, terminando-se como artéria espinhal ventral. A artéria mesencefálica emitiu ramos tectais para o lobo óptico e a artéria cerebelar dorsal.

Thirty turtle brains were used (Trachemys scripta elegans), injected with latex and stained in red, in order to systematize and describe the distribution and the territories of the internal carotid arteries and its main branches on the surface of the brain. The internal carotid arteries presented an intercarotic anastomosis and the internal ophthalmic artery. In the rostral third of the hypophysis, the internal carotid artery bifurcated into its two terminal branches, rostral and caudal. The rostral branch launched the rostral choroidal artery, the orbital artery and a sequence of midd le cerebral arteries. The rostral branch, after originating the last middle cerebral artery, continued as rostral cerebral artery and, when it reached the longitudinal fissure of the brain, showed an anastomosis with its contralateral homologous, resulting in the rostral communicating artery, making the first rostral closing of the cerebral arterial circle, when present. Immediately afterwards, the continuation of the rostral cerebral arteries anastomosed forming a rostral interhemispheric artery, closing for a second time the cerebral arterial circle, rostrally. The rostral interhemispheric artery, divided into medial rostral hemispheric arteries, each one launching a more ventral branch that projected rostrally, connecting ventrally to the vascular ring. The medial rostral hemispheric artery branched caudally and dorsally, ascending to the convex surface of the cerebral hemisphere, in its rostral pole. The main axis of the rostral medial hemispheric artery, usually received the anastomosis from the interhemispheric caudal artery deep branch. Their dorsal terminations, on the convex surface, anastomosed in osculum with the terminations of the last medial caudal hemispheric artery and the terminations of the dorsal terminal branch of the middle cerebral artery network. When the internal carotid artery projects dorsally at the level of the tuber cinereum, after issuing its rostral branch, it is continued caudally as its caudal branch. When the caudal branch projects caudally on the ventral side of the mesencephalic body, medial to the piriform lobe, it issues its first collateral branch, the caudal cerebral artery. The cerebral caudal artery launches hemispheric occipital branches, a caudal choroid branch (diencephalic) and pineal branches, continuing to the interior of the longitudinal fissure of the brain as the interhemispheric caudal artery. The interhemispheric caudal artery projects rostrally, usually from the inside of the longitudinal fissure, emitting hemispheric medial branches that ascend to the convex surface of the cerebral hemisphere. The deep branch of the caudal interhemispheric artery projects deeply into the cerebral longitudinal fissure in the rostral direction, anastomosing with the medial rostral hemispheric artery, branch of the rostral interhemispheric artery. After issuing the caudal cerebral artery, the caudal branch of the internal carotid artery contours laterally the apparent origin of the third cranial nerve, the oculomotor, issuing its main collateral branch caudolaterally, the mesencephalic artery, continuing caudomedially with a much thinner caliber, anastomosing with its contralateral homologous, originating the basilar artery. The small-caliber portion issues also its last collateral branch, the trigeminal artery. The anastomosis of the caudal branches close the cerebral arterial circle caudally. The basilar artery launched medullary branches. ending up as ventral spinal artery. The mesencephalic artery issued tectal branches to the optic lobe and the dorsal cerebellar artery.

Effects of a convertible to-and-fro and circle anesthetic system on cardiopulmonary variables in isoflurane anesthetized horses

Six healthy adult horses two male and four female, mean body weight of 424 + 44.1kg, were anesthetized with xylazine, ketamine/diazepam and isoflurane for 60 minutes using a convertible to-and-fro and circle system. Variables analyzed were arterial blood pH, carbon dioxide partial pressure (PaCO 2) and oxygen partial pressure (PaO2), respiratory rate(RR), and blood pressure. The horses were allowed to breath spontaneously, and were positioned in right lateral recumbency. The arterial O2 values were significantly higher during isoflurane anesthesia when compared to the baseline values, and significantly lower after induction with ketamine/diazepam although arterial hypoxemia were not present. The arterial PCO2 values were significantly higher from baseline values during isoflurane anesthesia occurring arterial hypercapnia and mild respiratoryacidosis. The arterial pH changes paralleled the changes in PaCO 2. Respiratory rate values were significantly lower during isoflurane anesthesia when compared to baseline values. All values remained within accepted range for lateral recumbent spontaneously breathing anesthetized horses. There were no significant differences between the circle and the to-and-fro system, demonstrating that either system is safe to maintain isoflurane anesthesia in adult horses.

Sistematização das artérias da base do encéfalo e suas fontes de suprimento sanguíneo em coelho da raça Nova Zelândia (Oryctolagus cuniculus)

Foram utilizados 30 encéfalos de coelhos Nova Zelândia (Oryctolagus cuniculus), injetados com látex, corado em vermelho, com objetivo de sistematizar as artérias da base do encéfalo e suas fontes de suprimento sanguíneo. Sistematizou-se a origem das fontes de suprimento sanguíneo para o encéfalo e as artérias (Aa) da face ventral do mesmo, tanto à direita (D) como à esquerda (E), com suas respectivas percentagens de aparecimento: o arco aórtico emitiu tronco braquiocefálico e artéria (A.) subclávia E (83,3%), ou tronco braquiocefálico, A. carótida comum E e A. subclávia E (16,7%). O tronco braquiocefálico lançou A. carótida comum D e E e A. subclávia D (83,3%), ou A. carótida comum D e A. subclávia D (16,7%). A. carótida comum dividiu-se em Aa carótidas externa e interna (96,7% D, 100% E). A. carótida interna D presente (96,7%) e ausente (3,3%), à E presente (100%). A. corióidea rostral D ramo colateral do ramo rostral da A. carótida interna D (83,3%), ramo colateral do ramo caudal da A. carótida interna D (16,7%), à E, ramo colateral do ramo rostral da A. carótida interna E (93,3%), ramo colateral do ramo caudal da A. carótida interna E (6,7%). A. cerebral média D e E ímpar (80%) e dupla (20%). A. cerebral rostral D com calibre médio (90%), calibre fino (6,7%), calibre muito fino (3,3%), à E, com calibre médio (76,7%), calibre fino (16,7%), calibre muito fino (6,7%). A. etmoidal interna ausente (73,3%), presente e ímpar (26,7%). A. cerebral caudal D, ímpar (66,7%), dupla (26,7%) e tripla (6,7%), à E, ímpar (63,3%) e dupla (36,7%). Ramos terminais das Aa. vertebrais D e E presentes (100%) formaram a A. basilar (100%). A. espinhal ventral ímpar presente (100%). A. cerebelar caudal D, ímpar (43,3%), ímpar com A. labiríntica isolada (26,7%) e dupla (30%), à E, ímpar (50%), ímpar com A. labiríntica isolada (6,7%), dupla (40%) e tripla (3,3%). A. trigeminal D e E presente (100%). A. cerebelar rostral D, ímpar (53,3%) e dupla (46,7%), à E, ímpar (63,3%) e dupla (36,7%). Observou-se que o círculo arterial cerebral do coelho foi fechado caudalmente (100%), rostralmente fechado (93,3%) e aberto (6,7%). O encéfalo foi suprido pelos sistemas vértebro-basilar e carotídeo

It was utilized 30 brains of New Zealand rabbits (Oryctolagus cuniculus), injected with red stained latex. The arteries to the blood supply¿s sources and to the ventral surface of the brain were systematized, on the right (R) and on the left (L) sides, with respective percentages of appearance: the aortic arch emitted the braquicephalic trunk and the left subclavian artery (83,3%); or the braquicephalic trunk, the left common carotid artery and the left subclavian artery (16,7%). The braquicephalic trunk emitted the right and the left commons carotids arteries and the right subclavian artery (83,3%); or the right common carotid artery and the right subclavian artery (16,7%). Commons carotid arteries divided into external and internal carotids arteries (96.7% on the R, 100% on the L.). The internal carotid artery, on the R, present (96,7%) and absent (3,3%), on the L, present (100%).The rostral corioidea artery, on the R, collateral branch of rostral branch of the internal carotid artery (83,3%), collateral branch of caudal branch of the internal carotid artey (16,7%), on the L, , collateral branch of rostral branch of the internal carotid artery (93,3%), collateral branch of caudal branch of the internal carotid artey (6,7%).The middle cerebral artery, on the R and on the L, single (80%) and double (20%).The rostral cerebral artery, on the R, with middle caliber (90%), thin caliber (6,7%) and much thin caliber (3,3%), on the L, with middle caliber (76,7%), thin caliber (16,7%) and much thin caliber (6,7%).The internal ethmoidal artery single, absent (73,3%), present and single (26,7%). The caudal cerebral artery, on the R, single (66,7%), double (26,7%) and triple (6,7%), on the L, single (63,3%) and double (36,,7%). The terminal branches of the right and the left vertebral arteries present (100%) were forming the basilar artery (100%). The ventral spinal artery present (100%).The caudal cerebellar artery, on the R, single (43,3%), single with labirintic artery isolated (26,7%) and double (30%), on the L, single (50%), single with labirintic artery isolated (6,7%), double (40%) and triple (3,3%).The trigeminal artery, on the R and on the L, present (100%).The rostral cerebellar artery, on the R, single (53,3%) and double (46,7%), on the L, single (63,3%) and double (36,7%). The rabbit¿s cerebral arterial circle was closed caudally (100%) and it was rostrally closed (93,3%) or open (6,7%). The brain was supplied by vertebral-basilar and carotid systems

O circuito arterial da base do encéfalo em suínos (Sus scrofa domesticus Linnaeus, 1758), formação e comportamento / The brain arterial circuit in swine (Sus scrofa domesticus Linnaeus, 1758), behavior ad formation

Estudamos em 40 suínos neonatos sem raça definida (SRD), 20 machos e 20 fêmeas, a formação vascular que se dispõe contornando o corpo mamilar, o túber cinéreo, a hipófise e o quiasma óptico na base do encéfalo. Os animais foram provenientes da Fazenda Santa Terezinha município de Uberlândia; 30 deles tiveram seus contingentes arteriais injetados com solução de Neoprene Látex 450, corada com pigmento específico, tendo sido fixados com solução de formal a 15% e dissecados; no restante injetou-se Acetato de Vinil corado seguindo-se corrosão em ácido sulfúrico a 30% os quais eram então lavados em água corrente. Os resultados mostraram que o circuito arterial é uma formação a partir da divisão da artéria carótida do encéfalo em ambos os antímeros, em seus ramos terminais rostral e caudal. Apresenta-se rostralmente em pequeno arco de concavidade medial (antímeros esquerdo e direito); caudalmente apresenta características morfológicas que fazem lembrar figura semelhante a um polígono - metade caudal de um hexágono - (53,3%) e no restante, figura simbólica de um coração (46,7%).0 circuito encontra-se fechado rostralmente pela presença constante da artéria comunicante rostral em todas as preparações e, caudalmente, pela presença dos ramos terminais esquerdo e direito da artéria basilar. Em 10%, além da presença dos ramos terminais esquerdo e direito da artéria basilar, o circuito arterial mostrou no local usual de bifurcação da artéria basilar, duas pequenas anastomoses.(AU)

Effects of a convertible to-and-fro and circle anesthetic system on cardiopulmonary variables in isoflurane anesthetized horses

Six healthy adult horses two male and four female, mean body weight of 424 + 44.1kg, were anesthetized with xylazine, ketamine/diazepam and isoflurane for 60 minutes using a convertible to-and-fro and circle system. Variables analyzed were arterial blood pH, carbon dioxide partial pressure (PaCO 2) and oxygen partial pressure (PaO2), respiratory rate(RR), and blood pressure. The horses were allowed to breath spontaneously, and were positioned in right lateral recumbency. The arterial O2 values were significantly higher during isoflurane anesthesia when compared to the baseline values, and significantly lower after induction with ketamine/diazepam although arterial hypoxemia were not present. The arterial PCO2 values were significantly higher from baseline values during isoflurane anesthesia occurring arterial hypercapnia and mild respiratoryacidosis. The arterial pH changes paralleled the changes in PaCO 2. Respiratory rate values were significantly lower during isoflurane anesthesia when compared to baseline values. All values remained within accepted range for lateral recumbent spontaneously breathing anesthetized horses. There were no significant differences between the circle and the to-and-fro system, demonstrating that either system is safe to maintain isoflurane anesthesia in adult horses.

Effects of a convertible to-and-fro and circle anesthetic system on cardiopulmonary variables in isoflurane anesthetized horses

Six healthy adult horses two male and four female, mean body weight of 424 + 44.1kg, were anesthetized with xylazine, ketamine/diazepam and isoflurane for 60 minutes using a convertible to-and-fro and circle system. Variables analyzed were arterial blood pH, carbon dioxide partial pressure (PaCO 2) and oxygen partial pressure (PaO2), respiratory rate(RR), and blood pressure. The horses were allowed to breath spontaneously, and were positioned in right lateral recumbency. The arterial O2 values were significantly higher during isoflurane anesthesia when compared to the baseline values, and significantly lower after induction with ketamine/diazepam although arterial hypoxemia were not present. The arterial PCO2 values were significantly higher from baseline values during isoflurane anesthesia occurring arterial hypercapnia and mild respiratoryacidosis. The arterial pH changes paralleled the changes in PaCO 2. Respiratory rate values were significantly lower during isoflurane anesthesia when compared to baseline values. All values remained within accepted range for lateral recumbent spontaneously breathing anesthetized horses. There were no significant differences between the circle and the to-and-fro system, demonstrating that either system is safe to maintain isoflurane anesthesia in adult horses.

Effects of a convertible to-and-fro and circle anesthetic system on cardiopulmonary variables in isoflurane anesthetized horses

Six healthy adult horses two male and four female, mean body weight of 424 + 44.1kg, were anesthetized with xylazine, ketamine/diazepam and isoflurane for 60 minutes using a convertible to-and-fro and circle system. Variables analyzed were arterial blood pH, carbon dioxide partial pressure (PaCO 2) and oxygen partial pressure (PaO2), respiratory rate(RR), and blood pressure. The horses were allowed to breath spontaneously, and were positioned in right lateral recumbency. The arterial O2 values were significantly higher during isoflurane anesthesia when compared to the baseline values, and significantly lower after induction with ketamine/diazepam although arterial hypoxemia were not present. The arterial PCO2 values were significantly higher from baseline values during isoflurane anesthesia occurring arterial hypercapnia and mild respiratoryacidosis. The arterial pH changes paralleled the changes in PaCO 2. Respiratory rate values were significantly lower during isoflurane anesthesia when compared to baseline values. All values remained within accepted range for lateral recumbent spontaneously breathing anesthetized horses. There were no significant differences between the circle and the to-and-fro system, demonstrating that either system is safe to maintain isoflurane anesthesia in adult horses.