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)

Systematization, distribution, and territories of the caudal cerebral artery on the surface of the brain in nutria (Myocastor coypus) / Sistematização, distribuição e territórios da artéria cerebral caudal na superfície do cérebro em Nutria (Myocastor coypus)

The nutria (Myocastor coypus) is a medium-sized, semi-aquatic rodent valued by the skin and meat industry. This study aimed to describe and systematize the caudal cerebral artery on the brain surface in nutria, establishing a standard model and its main variations in this species. The thirty animals used were euthanized according to animal welfare rules. The vessels were filled with latex stained with red pigment and the samples were fixed in formaldehyde. In nutria, the brain was vascularized by the vertebral basilar system. The terminal branches of the basilar artery originated the rostral cerebellar, caudal cerebral, rostral choroidal and middle cerebral arteries, and its terminal branch, the rostral cerebral artery. The terminal branch of the basilar artery projected the caudal cerebral artery, which is usually a single medium-caliber vessel, into the transverse fissure of the brain. The caudal cerebral artery was presented as a single (66.7% of the cases to the right and 76.7% to the left) and double vessel (33.3% of the cases to the right and 23.3% to the left). It originated the rostral mesencephalic artery, the proximal component, and the caudal inter-hemispheric artery. The terminal branches of the rostral and caudal tectal mesencephalic arteries formed a typical anastomotic network. The caudal inter-hemispheric artery emitted central branches, the caudal choroidal artery, hemispherical occipital arteries, rostral tectal mesencephalic branches and distal components, and anastomosed "in osculum" with the terminal branches of the rostral inter-hemispheric artery. The caudal choroidal artery anastomosed with the rostral choroidal artery, where it branched out on the thalamic mass, vascularizing all diencephalic structures and the hippocampus. The caudal cerebral artery and its terminal branches anastomosed with the terminal branches of the rostral and middle cerebral arteries in a restricted region of the caudal pole of the cerebral hemisphere. The vascularization area of the caudal cerebral artery and its central branches in the paleopallial of the piriform lobe is extremely restricted, caudomedially.(AU)

A nutria (Myocastor coypus) é um roedor semi-aquático de tamanho mediano, apreciado na indústria de peles e carne. Este trabalho tem por objetivo descrever e sistematizar a artéria cerebral caudal na superfície do cérebro em nutria, estabelecendo um modelo padrão e suas principais variações e territórios nesta espécie. Os trinta animais utilizados foram eutanasiados segundo as regras de bem-estar animal, os vasos foram preenchidos com látex, corado em vermelho e as peças foram fixadas em formoldeído. O cérebro foi vascularizado exclusivamente pelo sistema vértebro-basilar. Os ramos terminais da artéria basilar originaram as artérias cerebelar rostral, cerebral caudal, corióidea rostral, cerebral média e seu ramo terminal, a artéria cerebral rostral. O ramo terminal da artéria basilar lançou a artéria cerebral caudal, um vaso normalmente único, de médio calibre, para o interior da fissura transversa do cérebro. A artéria cerebral caudal foi um vaso único em 66,7% à direita e em 76,7% à esquerda e mostrou-se dupla em 33,3% à direita e em 23,3% à esquerda. Ela lançou a artéria tectal mesencefálica rostral, componente proximal e a artéria inter-hemisférica caudal. Os ramos terminais das artérias tectais mesencefálicas, rostral e caudal, formavam uma rede anastomótica típica. A artéria inter-hemisférica caudal lançou ramos centrais, a artéria corióidea caudal, as artérias hemisféricas occipitais, os ramos tectais mesencefálicos rostrais, componentes distais e anastomosou-se "em ósculo" com o ramo terminal da artéria inter-hemisférica rostral. A artéria corióidea caudal anastomosava-se com a artéria corióidea rostral, onde ramificavam-se sobre a massa talâmica, vascularizando todas as estruturas do diencéfalo e hipocampo. A artéria cerebral caudal com seus ramos terminais apresenta anastomoses com os ramos terminais das artérias cerebrais rostral e média em uma região restrita do pólo caudal do hemisfério cerebral. A área de vascularização da artéria cerebral caudal com seus ramos centrais no páleo-palio do lobo piriforme é extremamente restrita, caudo-medialmente ao mesmo.(AU)

Systematization, distribution, and territories of the caudal cerebral artery on the surface of the brain in nutria (Myocastor coypus) / Sistematização, distribuição e territórios da artéria cerebral caudal na superfície do cérebro em Nutria (Myocastor coypus)

The nutria (Myocastor coypus) is a medium-sized, semi-aquatic rodent valued by the skin and meat industry. This study aimed to describe and systematize the caudal cerebral artery on the brain surface in nutria, establishing a standard model and its main variations in this species. The thirty animals used were euthanized according to animal welfare rules. The vessels were filled with latex stained with red pigment and the samples were fixed in formaldehyde. In nutria, the brain was vascularized by the vertebral basilar system. The terminal branches of the basilar artery originated the rostral cerebellar, caudal cerebral, rostral choroidal and middle cerebral arteries, and its terminal branch, the rostral cerebral artery. The terminal branch of the basilar artery projected the caudal cerebral artery, which is usually a single medium-caliber vessel, into the transverse fissure of the brain. The caudal cerebral artery was presented as a single (66.7% of the cases to the right and 76.7% to the left) and double vessel (33.3% of the cases to the right and 23.3% to the left). It originated the rostral mesencephalic artery, the proximal component, and the caudal inter-hemispheric artery. The terminal branches of the rostral and caudal tectal mesencephalic arteries formed a typical anastomotic network. The caudal inter-hemispheric artery emitted central branches, the caudal choroidal artery, hemispherical occipital arteries, rostral tectal mesencephalic branches and distal components, and anastomosed "in osculum" with the terminal branches of the rostral inter-hemispheric artery. The caudal choroidal artery anastomosed with the rostral choroidal artery, where it branched out on the thalamic mass, vascularizing all diencephalic structures and the hippocampus. The caudal cerebral artery and its terminal branches anastomosed with the terminal branches of the rostral and middle cerebral arteries in a restricted region of the caudal pole of the cerebral hemisphere. The vascularization area of the caudal cerebral artery and its central branches in the paleopallial of the piriform lobe is extremely restricted, caudomedially.(AU)

A nutria (Myocastor coypus) é um roedor semi-aquático de tamanho mediano, apreciado na indústria de peles e carne. Este trabalho tem por objetivo descrever e sistematizar a artéria cerebral caudal na superfície do cérebro em nutria, estabelecendo um modelo padrão e suas principais variações e territórios nesta espécie. Os trinta animais utilizados foram eutanasiados segundo as regras de bem-estar animal, os vasos foram preenchidos com látex, corado em vermelho e as peças foram fixadas em formoldeído. O cérebro foi vascularizado exclusivamente pelo sistema vértebro-basilar. Os ramos terminais da artéria basilar originaram as artérias cerebelar rostral, cerebral caudal, corióidea rostral, cerebral média e seu ramo terminal, a artéria cerebral rostral. O ramo terminal da artéria basilar lançou a artéria cerebral caudal, um vaso normalmente único, de médio calibre, para o interior da fissura transversa do cérebro. A artéria cerebral caudal foi um vaso único em 66,7% à direita e em 76,7% à esquerda e mostrou-se dupla em 33,3% à direita e em 23,3% à esquerda. Ela lançou a artéria tectal mesencefálica rostral, componente proximal e a artéria inter-hemisférica caudal. Os ramos terminais das artérias tectais mesencefálicas, rostral e caudal, formavam uma rede anastomótica típica. A artéria inter-hemisférica caudal lançou ramos centrais, a artéria corióidea caudal, as artérias hemisféricas occipitais, os ramos tectais mesencefálicos rostrais, componentes distais e anastomosou-se "em ósculo" com o ramo terminal da artéria inter-hemisférica rostral. A artéria corióidea caudal anastomosava-se com a artéria corióidea rostral, onde ramificavam-se sobre a massa talâmica, vascularizando todas as estruturas do diencéfalo e hipocampo. A artéria cerebral caudal com seus ramos terminais apresenta anastomoses com os ramos terminais das artérias cerebrais rostral e média em uma região restrita do pólo caudal do hemisfério cerebral. A área de vascularização da artéria cerebral caudal com seus ramos centrais no páleo-palio do lobo piriforme é extremamente restrita, caudo-medialmente ao mesmo.(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)

Anatomic study of the arterial vascularization of the brain base of paca (Cuniculus paca) / Estudo anatômico da vascularização arterial da base do encéfalo da paca (Cuniculus paca)

Paca (Cuniculus paca Linnaeus, 1766), rodent belong to the Cuniculidae family, has encouraged numerous scientific researches and for this reason could be an experimental model in both human and veterinary areas. And recently, the economic exploitation of the meat cuts, has being direct implication in its zootechnical importance. However, no anatomical descriptions regarding the vascularization of the base of the brain in this rodent has being found. Thus, the aim of the present study was to describe the arteries and the pattern of the vasculature and to compare it with the other species already established in the literature. For this, five pacas, donated by the Unesp Jaboticabal Wildlife Sector, were euthanized followed by the vascular arterial system was injected with red-stained-centrifuged latex by the common carotid artery. After craniectomy, the brains were removed and the arteries were identified and, in addition, compared with those described in other animal species. The presence of the right and left vertebral arteries, close to the medulla oblongata, was detected, originating the basilar artery, which divided into the terminal branches of the right and left basilar artery. Ventral to the optic tract there was the right internal carotid artery and the left, dividing the middle cerebral artery and left rostral and right; dorsal to the optic chiasm, the medial branch of the rostral cerebral arteries was identified. Based on the results, it is concluded that the vascularization of the paca brain base is supplied by the carotid and vertebrobasilar system.(AU)

A paca (Cuniculus paca Linnaeus 1766), roedor da família Cuniculidae, tem encorajado inúmeras pesquisas científicas, tornando-a modelo experimental tanto na área humana quanto na veterinária, além da recente exploração econômica de seus cortes cárneos, que favoreceu diretamente sua importância zootécnica. No entanto, não há até o momento, descrições anatômicas referentes à padronização da vascularização da base do encéfalo neste roedor. Assim, o objetivo do presente trabalho foi realizar tal delineamento arterial nessa região do sistema nervoso central e compará-lo com as demais espécies já estabelecidas na literatura. Para isso, foram eutanasiadas cinco pacas doadas pelo setor de Animais Silvestres da Unesp Jaboticabal, as quais foram submetidas posteriormente à injeção de látex centrifugado e corante líquido xadrez vermelho, pela artéria carótida comum. Após craniectomia e segregação do encéfalo de todos os cadáveres, realizou-se a identificação das artérias presentes na base deste órgão e, ademais, comparação destas com as descritas cientificamente em outras espécies animais. Detectou-se a presença das artérias vertebral direita e esquerda, próximas à medula oblonga, originando a artéria basilar, que se dividiu nos ramos terminais da artéria basilar direito e esquerdo. Ventral ao trato óptico verificou-se a artéria carótida interna direita e esquerda dividindo-se na artéria cerebral média e rostral direita e esquerda; ainda, dorsal ao quiasma óptico, identificou-se o ramo medial das artérias cerebrais rostrais. Com base nos resultados obtidos, conclui-se que a vascularização da base do encéfalo da paca é suprida pelo sistema carotídeo e vertebro-basilar.(AU)

Anatomic study of the arterial vascularization of the brain base of paca (Cuniculus paca) / Estudo anatômico da vascularização arterial da base do encéfalo da paca (Cuniculus paca)

Paca (Cuniculus paca Linnaeus, 1766), rodent belong to the Cuniculidae family, has encouraged numerous scientific researches and for this reason could be an experimental model in both human and veterinary areas. And recently, the economic exploitation of the meat cuts, has being direct implication in its zootechnical importance. However, no anatomical descriptions regarding the vascularization of the base of the brain in this rodent has being found. Thus, the aim of the present study was to describe the arteries and the pattern of the vasculature and to compare it with the other species already established in the literature. For this, five pacas, donated by the Unesp Jaboticabal Wildlife Sector, were euthanized followed by the vascular arterial system was injected with red-stained-centrifuged latex by the common carotid artery. After craniectomy, the brains were removed and the arteries were identified and, in addition, compared with those described in other animal species. The presence of the right and left vertebral arteries, close to the medulla oblongata, was detected, originating the basilar artery, which divided into the terminal branches of the right and left basilar artery. Ventral to the optic tract there was the right internal carotid artery and the left, dividing the middle cerebral artery and left rostral and right; dorsal to the optic chiasm, the medial branch of the rostral cerebral arteries was identified. Based on the results, it is concluded that the vascularization of the paca brain base is supplied by the carotid and vertebrobasilar system.(AU)

A paca (Cuniculus paca Linnaeus 1766), roedor da família Cuniculidae, tem encorajado inúmeras pesquisas científicas, tornando-a modelo experimental tanto na área humana quanto na veterinária, além da recente exploração econômica de seus cortes cárneos, que favoreceu diretamente sua importância zootécnica. No entanto, não há até o momento, descrições anatômicas referentes à padronização da vascularização da base do encéfalo neste roedor. Assim, o objetivo do presente trabalho foi realizar tal delineamento arterial nessa região do sistema nervoso central e compará-lo com as demais espécies já estabelecidas na literatura. Para isso, foram eutanasiadas cinco pacas doadas pelo setor de Animais Silvestres da Unesp Jaboticabal, as quais foram submetidas posteriormente à injeção de látex centrifugado e corante líquido xadrez vermelho, pela artéria carótida comum. Após craniectomia e segregação do encéfalo de todos os cadáveres, realizou-se a identificação das artérias presentes na base deste órgão e, ademais, comparação destas com as descritas cientificamente em outras espécies animais. Detectou-se a presença das artérias vertebral direita e esquerda, próximas à medula oblonga, originando a artéria basilar, que se dividiu nos ramos terminais da artéria basilar direito e esquerdo. Ventral ao trato óptico verificou-se a artéria carótida interna direita e esquerda dividindo-se na artéria cerebral média e rostral direita e esquerda; ainda, dorsal ao quiasma óptico, identificou-se o ramo medial das artérias cerebrais rostrais. Com base nos resultados obtidos, conclui-se que a vascularização da base do encéfalo da paca é suprida pelo sistema carotídeo e vertebro-basilar.(AU)

Systematization of the brain base arteries in nutria (Myocastor coypus) / Sistematização das artérias da base do encéfalo em nutria (Myocastor coypus)

Background: The nutria (Myocastor coypus) is a medium-size, semi-aquatic rodent, valued in skin and meat industry. The brain circulation has been well studied in rodents but not in nutria. To understand and compare the phylogenetic development of the arteries of the base of the brain in rodents, this paper aims to describe and systematize these arteries, establishing a standard model and its main variations in nutria.Materials, Methods & Results: Following approval by the Ethics Committee of Federal University of Rio Grande do Sul, thirty nutrias from a commercial establishment authorized by Brazilian Institute of Environment and Natural Resources (IBAMA) were studied. For euthanasia, was applied heparin (10000 U.I for animal), intraperitoneally, and after thirty minutes the animals ware sedated with acepromazine (0.5 mg/kg) and meperidine (20 mg/kg), intramuscularly. After sedation, they were euthanized with thiopental sodium (120 mg/kg) and lidocaine (10 mg/mL), intraperitoneally. The heart was accessed, the cardiac apex was sectioned, the aorta was cannulated via the left ventricle and clamped close to the diaphragm, and the arterial system was washed with saline solution and filled with latex. The animals were submerged in water for latex polymerization, the trunk was sectioned, the skin removed and a bony window was opened in the skull vault. The pieces were fixed in formaldehyde. The brains were removed, and schematic drawings of the arteries from the base of the brain were made for elaboration of the results. The nutria’s brain was vascularized by the vertebro-basilar system. The terminal branches of the right and left vertebral artery were anastomosed on the ventral surface of the medulla oblongata, forming the basilar artery, and caudally the ventral spinal artery.[...]

Systematization of the brain base arteries in nutria (Myocastor coypus) / Sistematização das artérias da base do encéfalo em nutria (Myocastor coypus)

Background: The nutria (Myocastor coypus) is a medium-size, semi-aquatic rodent, valued in skin and meat industry. The brain circulation has been well studied in rodents but not in nutria. To understand and compare the phylogenetic development of the arteries of the base of the brain in rodents, this paper aims to describe and systematize these arteries, establishing a standard model and its main variations in nutria.Materials, Methods & Results: Following approval by the Ethics Committee of Federal University of Rio Grande do Sul, thirty nutrias from a commercial establishment authorized by Brazilian Institute of Environment and Natural Resources (IBAMA) were studied. For euthanasia, was applied heparin (10000 U.I for animal), intraperitoneally, and after thirty minutes the animals ware sedated with acepromazine (0.5 mg/kg) and meperidine (20 mg/kg), intramuscularly. After sedation, they were euthanized with thiopental sodium (120 mg/kg) and lidocaine (10 mg/mL), intraperitoneally. The heart was accessed, the cardiac apex was sectioned, the aorta was cannulated via the left ventricle and clamped close to the diaphragm, and the arterial system was washed with saline solution and filled with latex. The animals were submerged in water for latex polymerization, the trunk was sectioned, the skin removed and a bony window was opened in the skull vault. The pieces were fixed in formaldehyde. The brains were removed, and schematic drawings of the arteries from the base of the brain were made for elaboration of the results. The nutrias brain was vascularized by the vertebro-basilar system. The terminal branches of the right and left vertebral artery were anastomosed on the ventral surface of the medulla oblongata, forming the basilar artery, and caudally the ventral spinal artery.[...](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)

Arterial Vascularization of the Base of the Brain in Galea (Galea spixii)

Background: Galea (Galea spixii) are rodents which are especially distributed in the northeastern region of Brazil, and have economic importance as their meat is used as a source of protein by the regional population.  Currently, they have received attention from researchers in studies involving their morphology. Thus, seeking to contribute information that supports their sanitary management in addition to the lack of literature on their nervous system, our objective was to describe the arterial vascularization of the base of the brain in this species, in order to identify the arterial pattern and arterial circuit behavior, as well as possible variations in these vessels.Materials, Methods & Results: Brains were obtained from 20 animals (10 males and 10 females) aged between 11 and 12 months, obtained from the Wild Animal Multiplication Center (CEMAS) of the Federal Rural Semi-Arid University (UFERSA), under the approval of CEUA/UFERSA (case number 23.091.000653/2014-26 and opinion number 15/2014), euthanized according to anesthetic protocol recommended for rodents (resolution number 714/2002 of the CFMV/ UFERSA) and preserved frozen in a freezer for an average period of 30 days. The animals were thawed and a longitudinal incision was performed in the thoracic region to allow exposure of the aortic arch. Next, they were cannulated in the cranial direction and injected with

Vascularização arterial da base do encéfalo do gerbil (Meriones unguiculatus Milne-Edwards, 1867) / Arterial vascularization of the base of the cerebrum of mongolian gerbils(Meriones unguiculatus Milne-Edwards, 1867)

Objetivou-se descrever e sistematizar as artérias da base do encéfalo. Foram utilizados dez gerbils que se encontravamarmazenados em freezer no laboratório de Morfofisiologia Animal Aplicada da Universidade Federal Rural do Semiárido. Osanimais foram descongelados, incisados na linha mediana para identificação do ventrículo esquerdo, o qual foi perfurado einjetados 3ml de Látex Neoprene 650 na concentração de 20% e no pigmento vermelho. Posteriormente aguardou-se cerca de 1minuto em virtude da polimerização do Látex e logo após foram fixados por imersão em solução aquosa de Formaldeído a 3,7% eapós 72 horas, tiveram os encéfalos removidos da calota craniana para análise de sua superfície ventral. Foi visto que o sistemavertebrobasilar e carótico estiveram presentes em todos os animais analisados, mostrando-se responsável pela vascularizaçãodo encéfalo caudal e rostral, respectivamente. As principais artérias observadas no modelo padrão incluem as ímpares: basilar,espinhal ventral, ramo medial da artéria cerebral rostral e as pares: vertebral, cerebelar caudal, cerebelar média, trigeminal,cerebelar rostral, ramo terminal da basilar, carótida interna, cerebral caudal, hipofisária, cerebral média, cerebral rostral, lateral dobulbo olfatório e etmoidal interna. Conclui-se com base nos resultados que a irrigação da superfície ventral encefálica do gerbilfoi suprida pelos sistemas vertebro-basilar e carótico de forma equivalente, pertencendo assim ao modelo do tipo II. O circuitoarterioso apresentou-se aberto caudalmente e fechado rostralmente, fato que difere do relatado em roedores como capivara,cutia, preá, chinchila e nutria.(AU)

The objective was to describe and systematize the arteries of the base of the brain. Ten gerbils were used, which were stored in afreezer in the Laboratory of Applied Animal Morphophysiology of the Federal Rural Semi-Arid University. The animals were thawed,incised in the midline to identify the left ventricle, which was punctured and injected 3 ml of Latex Neoprene 650 at a concentrationof 20% and red pigment. After about one minute the polymerization of the Latex was delayed and afterwards fixed by immersionin 3.7% aqueous Formaldehyde solution and after 72 hours the brain was removed from the skull cap for analysis of its ventralsurface. It was observed that the vertebro-basilar and carotid system were present in all animals analyzed, being responsible forthe vascularization of the caudal and rostral encephalon, respectively. The main arteries observed in the standard model includethe odd: basilar, ventral spinal, medial branch of the rostral cerebral artery and, the pairs: vertebral, cerebellar caudal, cerebellarmedial, trigeminal, cerebellar rostral, terminal branch of the basilar, internal carotid, caudal cerebral, Pituitary, middle cerebral, rostral,lateral, olfactory and internal ethmoidal. Based on the results, the irrigation of the ventral brain surface of the gerbil was suppliedby the vertebro-basilar and carotic systems in an equivalent way, thus belonging to the type II model. The arterial circuit was opencaudally and closed rostrally, a fact that differs from that reported in rodents such as capybara, agouti, cavy, chinchilla and nutria.(AU)

Vascularização arterial da base do encéfalo de preá (Galea spixii) / Arterial vascularization of the base of the brain in galea (Galea spixii)

Background: Galea (Galea spixii) are rodents which are especially distributed in the northeastern region of Brazil, and have economic importance as their meat is used as a source of protein by the regional population. Currently, they have received attention from researchers in studies involving their morphology. Thus, seeking to contribute information that supports their sanitary management in addition to the lack of literature on their nervous system, our objective was to describe the arterial vascularization of the base of the brain in this species, in order to identify the arterial pattern and arterial circuit behavior, as well as possible variations in these vessels. Materials, Methods & Results: Brains were obtained from 20 animals (10 males and 10 females) aged between 11 and 12 months, obtained from the Wild Animal Multiplication Center (CEMAS) of the Federal Rural Semi-Arid University (UFERSA), under the approval of CEUA/UFERSA (case number 23.091.000653/2014-26 and opinion number 15/2014), euthanized according to anesthetic protocol recommended for rodents (resolution number 714/2002 of the CFMV/ UFERSA) and preserved frozen in a freezer for an average period of 30 days. The animals were thawed and a longitudinal incision was performed in the thoracic region to allow exposure of the aortic arch. Next, they were cannulated in the cranial direction and injected with Noprene Latex “650” stained with water-based white or red pigment. The animals were subsequently fixed in 3.7% aqueous formaldehyde solution for 48 h, and soon after the brain skull cap was dissected and removed, which was then analyzed, photographed and sketched. Of the 20 animals evaluated, 100% presented vertebrobasilar system responsible for encephalic irrigation of the rostral and caudal regions, and anastomosis of the left internal carotid artery was found in only […]

Vascularização arterial da base do encéfalo de preá (Galea spixii) / Arterial vascularization of the base of the brain in galea (Galea spixii)

Background: Galea (Galea spixii) are rodents which are especially distributed in the northeastern region of Brazil, and have economic importance as their meat is used as a source of protein by the regional population. Currently, they have received attention from researchers in studies involving their morphology. Thus, seeking to contribute information that supports their sanitary management in addition to the lack of literature on their nervous system, our objective was to describe the arterial vascularization of the base of the brain in this species, in order to identify the arterial pattern and arterial circuit behavior, as well as possible variations in these vessels. Materials, Methods & Results: Brains were obtained from 20 animals (10 males and 10 females) aged between 11 and 12 months, obtained from the Wild Animal Multiplication Center (CEMAS) of the Federal Rural Semi-Arid University (UFERSA), under the approval of CEUA/UFERSA (case number 23.091.000653/2014-26 and opinion number 15/2014), euthanized according to anesthetic protocol recommended for rodents (resolution number 714/2002 of the CFMV/ UFERSA) and preserved frozen in a freezer for an average period of 30 days. The animals were thawed and a longitudinal incision was performed in the thoracic region to allow exposure of the aortic arch. Next, they were cannulated in the cranial direction and injected with Noprene Latex “650” stained with water-based white or red pigment. The animals were subsequently fixed in 3.7% aqueous formaldehyde solution for 48 h, and soon after the brain skull cap was dissected and removed, which was then analyzed, photographed and sketched. Of the 20 animals evaluated, 100% presented vertebrobasilar system responsible for encephalic irrigation of the rostral and caudal regions, and anastomosis of the left internal carotid artery was found in only […](AU)

Arterial vascularization of the brain of the agouti (Dasyprocta aguti Linnaeus, 1766) / Vascularização arterial da base do encéfalo de cutias (Dasyprocta aguti Linnaeus, 1766)

The agouti, a rodent that is geographically distributed throughout South America, is greatly valued for its meat. This paper describes the arterial vascularization of the base of the agoutis brain, characterizing behavior, and arterial origin and distribution. Ten animals from the Center for the Multiplication of Wild Animals (CEMAS/UFERSA) were used and the study was approved by SISBIO (report number 32413-1) and the Ethics Committee on Animal Use (CEUA/UFERSA) (protocol 02/2010). After euthanasia, the animals were incised in the thoracic cavity by an injection of red-stained Neoprene latex 650 and the skulls were subsequently opened. The brains were extracted from the skulls for ventral surface analysis and then fixed in an aqueous 10% formaldehyde solution. The agoutis arterial vascularization of the brain has two main components, namely the carotid and vertebrobasilar systems. The agoutis carotid system accounts for vascularization of almost the entire forebrain, while the vertebrobasilar system accounts for vascularization of almost the entire posterior brain (medulla oblongata, pyramid, trapezoid body, cerebellum, bridge, and part of the third caudal section of the forebrain) through the caudal cerebral arteries originating from the terminal branches of the basilar artery. The main arteries on the brain surface include the basilar artery, which is unique, and the arterial pairs, specifically the vertebral arteries, cerebellar caudal arteries, trigeminal artery, rostral cerebellar artery, basilar terminal branch artery, cerebral caudal artery, communicating caudal branch of the cerebral carotid artery, cerebral carotid artery, communicating branch rostral cerebral carotid artery, choroidal rostral artery, medial branch of the communicating branch rostral artery, internal ophthalmic artery, middle cerebral artery, and rostral cerebral artery.(AU)

A cutia é um roedor, que se distribui geograficamente por quase toda América Latina, sendo apreciada pelo sabor da sua carne. Neste trabalho objetivou-se descrever a vascularização arterial da base do encéfalo de cutias, caracterizando o comportamento, origem e distribuição das artérias componentes. Foram utilizados 10 animais do Centro de Multiplicação de Animais Silvestres (CEMAS/UFERSA), pesquisa aprovada pela Comissão de Ética no Uso de Animais (CEUA/ UFERSA- n° 02/2010) e pelo SISBIO (N°32413-1). Após eutanásia, os animais foram incisados na cavidade torácica para injeção de Neoprene látex 650 corado na cor vermelha e posterior abertura da calota craniana. Os encéfalos foram extraídos do crânio para análise da sua face ventral e logo fixados em solução aquosa de formaldeído a 10%. A vascularização arterial do encéfalo da cutia apresenta dois componentes principais, o sistema carótico e o vértebro-basilar. O sistema carótico na cutia é responsável pela vascularização do cérebro anterior em quase sua totalidade. O sistema vértebro-basilar é responsável pela vascularização do cérebro posterior (medula oblonga, pirâmide, corpo trapezóide, o cerebelo e ponte e parte do terço caudal do cérebro anterior), através das artérias cerebrais caudais, originárias dos ramos terminais da artéria basilar. As principais artérias presentes na superfície do encéfalo incluem a basilar que é ímpar, e as pares: artérias vertebrais, cerebelar caudal, trigemial, cerebelar rostral, ramo terminal da basilar, cerebral caudal, ramo comunicante caudal da carótida cerebral, carótida cerebral, ramo comunicante rostral da carótida cerebral, corióidearostral, ramo medial do ramo comunicante rostral, oftálmica interna, cerebral média e artéria cerebral rostral.(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.

Anatomia do circuito arterial do encéfalo em Tamanduá-mirim

The arterial circuit of the brain is of great importance because it is responsible for vascularization of the brain and this is the main organ of the central nervous system and responsible for receiving and processing information. The species was chosen because it is a mammal belonging to the Xenarthra order and the members of this order are little studied because of the difficulty of access to these animals. To develop this work were studied five specimens of lesser anteater (Tamandua tetradactyla). The material had the arterial system filled with Neoprene latex stained in red, fixed in aqueous solution of 10% paraformaldehyde and dissected for vessels systematization. The encephalon arterial circuit of lesser anteater surrounds the mammillary body, the interpeduncular fossa, tuber cinereum, hypophysis and optic chiasm. The rostral portion of this circuit is characterized by rostral branches of internal carotid arteries and the caudal portion is formed by caudal communicant arteries from internal carotid artery. This animal species had a type II of encephalic irrigation with participation of internal carotid arteries and vertebrobasilar system to formation of arterial circuit.

O circuito arterial do encéfalo é de grande importância, pois é responsável pela vascularização do encéfalo, sendo este o principal órgão do sistema nervoso central e responsável por receber e processar informações. A espécie estudada foi escolhida por tratar-se de um mamífero pertencente à ordem Xenarthra e os integrantes dessa ordem são pouco estudados, devido à dificuldade de acesso a esses animais. Para desenvolver este trabalho, foram estudados cinco espécimes de Tamanduá-mirim (Tamandua tetradactyla). O material teve o sistema arterial injetado com látex Neoprene 650, corado em vermelho e fixado em solução aquosa de Formaldeído 10%, sendo posteriormente dissecados para sistematização dos vasos. O circuito arterial da base do encéfalo do tamanduá-mirim circunda o corpo mamilar, a fossa interpenduncular, o túber cinéreo, a hipófise e o quiasma óptico. A porção rostral desse circuito é caracterizada pelos ramos rostrais das artérias carótidas internas e a porção caudal é constituída pelas artérias comunicantes caudais e ramos caudais da artéria carótida interna. Esta espécie animal apresenta o tipo II de irrigação encefálica no qual existe a participação das artérias carótidas internas e do sistema vértebro-basilar para a formação do circuito arterial.

Anatomia do circuito arterial do encéfalo em Tamanduá-mirim

The arterial circuit of the brain is of great importance because it is responsible for vascularization of the brain and this is the main organ of the central nervous system and responsible for receiving and processing information. The species was chosen because it is a mammal belonging to the Xenarthra order and the members of this order are little studied because of the difficulty of access to these animals. To develop this work were studied five specimens of lesser anteater (Tamandua tetradactyla). The material had the arterial system filled with Neoprene latex stained in red, fixed in aqueous solution of 10% paraformaldehyde and dissected for vessels systematization. The encephalon arterial circuit of lesser anteater surrounds the mammillary body, the interpeduncular fossa, tuber cinereum, hypophysis and optic chiasm. The rostral portion of this circuit is characterized by rostral branches of internal carotid arteries and the caudal portion is formed by caudal communicant arteries from internal carotid artery. This animal species had a type II of encephalic irrigation with participation of internal carotid arteries and vertebrobasilar system to formation of arterial circuit.

O circuito arterial do encéfalo é de grande importância, pois é responsável pela vascularização do encéfalo, sendo este o principal órgão do sistema nervoso central e responsável por receber e processar informações. A espécie estudada foi escolhida por tratar-se de um mamífero pertencente à ordem Xenarthra e os integrantes dessa ordem são pouco estudados, devido à dificuldade de acesso a esses animais. Para desenvolver este trabalho, foram estudados cinco espécimes de Tamanduá-mirim (Tamandua tetradactyla). O material teve o sistema arterial injetado com látex Neoprene 650, corado em vermelho e fixado em solução aquosa de Formaldeído 10%, sendo posteriormente dissecados para sistematização dos vasos. O circuito arterial da base do encéfalo do tamanduá-mirim circunda o corpo mamilar, a fossa interpenduncular, o túber cinéreo, a hipófise e o quiasma óptico. A porção rostral desse circuito é caracterizada pelos ramos rostrais das artérias carótidas internas e a porção caudal é constituída pelas artérias comunicantes caudais e ramos caudais da artéria carótida interna. Esta espécie animal apresenta o tipo II de irrigação encefálica no qual existe a participação das artérias carótidas internas e do sistema vértebro-basilar para a formação do circuito arterial.

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.

Proposal of anatomical terminology to call the arteries of the base of the encephalon in the monkey (Cebus paella L., 1766) / Nomenclatura proposta para denominar as artérias da base do encéfalo do macaco-prego (Cebus apella L., 1766)

Arteries of the encephalon basis of 30 monkeys (Cebus paella) were studied. Arteries were injected with colored latex, fixed in formaldehyde solution at 10% and dissected under magnifying lenses. Since the animals died from natural causes they had been previously used in other experiments. Human and veterinary anatomical terminology and literature were used as a reference for the determination of vessels studied in the primates. Arteries of the encephalon base represent division branches of three vascular pedicules: the right and left internal carotid arteries and the basilar system. Vessels in the basilar system of the animal were called vertebral arteries; anterior spinal artery; anterior and posterior cerebelar arteries; pontine arteries; satellite cerebelar arteries; caudal and cranial cerebelar arteries. The basilar artery bifurcates into two posterior cerebral arteries (100%). The caudal area of the encephalons arterial circuit is thus constituted. Linking between the vertebro-basilar and the carotid segments is done by the posterior communicating artery, that caudally anastomizes (100%) with the posterior cerebral artery. The internal carotid artery gives origin to the posterior communicating artery. The right and left internal carotid artery (intracranial portion) compounds the carotid system. The following vessels were identified: middle cerebral artery; anterior cere

Estudaram-se as artérias da base do encéfalo do Cebus apella em 30 animais, vindos a óbito por morte natural no Zoológico de São Paulo e coletados durante 10 anos. O material recebeu injeção de látex corado, fixado em formol a 10%, e foi dissecado sob lupa. Encontramos dificuldade e denominar estes vasos. As terminologias anatômicas humana e veterinária e a recuperação da literatura nos serviram de base para sugerirmos uma denominação que se adequasse ao modelo arterial desse primata. Os resultados nos permitiram verificar, no circuito arterial da base do encéfalo, segmento caudal ou vértebro-basilar as artérias (a): a. vertebral, suas partes (pé-vertebral, cervical, atlântica e intracraniana com ramos meníngeos) e seus ramos (a. espinhal anterior, a. cerebelar inferior caudal, ramos para a medula oblonga); a. basilar e seus ramos (a. cerebelar inferior rostral, a. pontinas, a. cerebelar superior satélite, ilhas artérias, a. cerebelar anterior, a. cerebelar posterior); e no segmento rostral ou carótico os vasos: a. carótida interna (parte cerebral); a. comunicante posterior; a. coróidea; a. cerebral média; a. cerebral anterior; a. olfatória; a. inter-hemisférica. A análise dos resultados nos permitiu considerar que o Cebus apella apresentou um padrão arterial de relativa estabilidade morfológica em função das poucas variações encontradas nos vasos formadores dos circuitos arter