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1.
Acta sci. vet. (Impr.) ; 50(supl.1): 785, 2022. ilus
Artigo em Inglês | VETINDEX | ID: biblio-1370266

Resumo

Background: Chemodectomas, better known as tumors of the base of the heart, arise from aortic bodies, respiratory chemoreceptors located near or inside the aortic arch or originate from receptors located in the carotid arteries. Relatively rare, they affect dogs and, to a lesser extent, cats. They gain great importance when they influence the function of the cardiovascular system, with animals showing clinical signs related to congestive heart failure. Clinical diagnosis is based on symptomatology and complementary tests such as radiography, electrocardiography and echocardiography, while the definitive diagnosis is obtained by cytological and histopathological exams. This study aims to reports a case of malignant chemodectoma in a bitch, whose main symptomatology was neurological and not cardiovascular. Case: A 1-year-old Rottweiler bitch was attended with neurological alterations compatible with vestibular syndrome, hyporexia, dysphagia, apathy, melena, emesis, and purulent nasal discharge on the right nostril. On physical examination, the animal showed depressed level of consciousness, poor body condition, bilateral quemosis, paralysis of the right eye, inspiratory dyspnea and muffling of cardiac auscultation, besides a subcutaneous nodule between the scapulae. On neurological evaluation, horizontal nystagmus, head tilt to the right side, ventromedial strabismus and facial nerve paralysis on the right side were observed so that the localization of the lesion was set in peripheral vestibular system. During anesthesia for esophageal tube placement, a mass from the hard palate to the oropharynx was noted, making endotracheal intubation impossible to perform. Biopsy of this nodule was performed, and tracheostomy was indicated, but the owner opted for euthanasia before the procedure. Necropsy revealed white soft masses in the bilateral retromandibular region, on the subcutaneous tissue near the scapulae, in the right ear and since nasopharynx to the soft palate, in addition to sparse white nodules in the heart, lung, carotid artery, kidneys, right ovary, mesentery near to the spleen, and axillary lymph node. Histologically, the nodules were characterized by neoplastic cells population organized in short bundles or cords, arranged around small blood vessels surrounded by delicate connective tissue. Neoplastic cells infiltrated muscles and blood and lymphatic vessels were filled by multiple neoplastic emboli. The histological pattern of the cells allowed the diagnosis of chemodectoma. Discussion: The bitch from this case had 1-year-old when diagnosed with chemodectoma, differently from most cases from literature, that are between 7 to 15 years old. Furthermore, primarily cardiac tumors are considered rare, being chemodectoma the most common, often reported in Boxer and Boston Terrier dogs, but unusual in Rottweilers. Despites some articles mentioning seizure and Horner's Syndrome secondary to a carotid body chemodectoma, neurological signs are not commonly observed in these cases. The presence of the tumor in the middle ear region of the right side supports the occurrence of peripheral vestibular syndrome and facial nerve paralysis on the same side. Because it is a neoplasm that is usually detected late during the course of the disorder, most patients either cannot obtain diagnosis in vivo, as in this reported animal, which was in such a critical condition that underwent euthanasia, or there are no more possible therapeutic choices. In the patient described, there were numerous metastatic masses and nodules spread throughout the body. Although the typical clinical signs in animals with chemodectomas are often related to heart disease, neurological signs may also be present. This report emphasizes the importance of chemodectoma being included as a differential diagnosis in young dogs and even in breeds such as Rottweiler.


Assuntos
Animais , Feminino , Cães , Síndromes do Arco Aórtico/veterinária , Doenças Vestibulares/veterinária , Paraganglioma Extrassuprarrenal/veterinária , Doenças do Sistema Nervoso/veterinária
2.
Pesqui. vet. bras ; 40(4): 315-323, Apr. 2020. tab, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1135615

Resumo

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)


Assuntos
Animais , Encéfalo/irrigação sanguínea , Círculo Arterial do Cérebro/anatomia & histologia , Alouatta/anatomia & histologia
3.
Pesqui. vet. bras ; 40(9): 733-737, Sept. 2020. tab, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1143418

Resumo

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)


Assuntos
Animais , Encéfalo/irrigação sanguínea , Artérias Cerebrais/anatomia & histologia , Cuniculidae/anatomia & histologia
4.
Pesqui. vet. bras ; 40(9): 733-737, Sept. 2020. tab, ilus
Artigo em Inglês | VETINDEX | ID: vti-31773

Resumo

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)


Assuntos
Animais , Encéfalo/irrigação sanguínea , Artérias Cerebrais/anatomia & histologia , Cuniculidae/anatomia & histologia
5.
Pesqui. vet. bras ; 40(4): 315-323, Apr. 2020. tab, ilus
Artigo em Inglês | VETINDEX | ID: vti-29438

Resumo

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)


Assuntos
Animais , Encéfalo/irrigação sanguínea , Círculo Arterial do Cérebro/anatomia & histologia , Alouatta/anatomia & histologia
6.
J. venom. anim. toxins incl. trop. dis ; 26: e20190070, 2020. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1101267

Resumo

Intrathecal injection of voltage-sensitive calcium channel blocker peptide toxins exerts analgesic effect in several animal models of pain. Upon intrathecal administration, recombinant Phα1ß exerts the same analgesic effects as the those of the native toxin. However, from a clinical perspective, the intrathecal administration limits the use of anesthetic drugs in patients. Therefore, this study aimed to investigate the possible antinociceptive effect of intravenous recombinant Phα1ß in rat models of neuropathic pain, as well as its side effects on motor, cardiac (heart rate and blood pressure), and biochemical parameters. Methods: Male Wistar rats and male Balb-C mice were used in this study. Giotto Biotech® synthesized the recombinant version of Phα1ß using Escherichia coli expression. In rats, neuropathic pain was induced by chronic constriction of the sciatic nerve and paclitaxel-induced acute and chronic pain. Mechanical sensitivity was evaluated using von Frey filaments. A radiotelemeter transmitter (TA11PA-C10; Data Sciences, St. Paul, MN, USA) was placed on the left carotid of mice for investigation of cardiovascular side effects. Locomotor activity data were evaluated using the open-field paradigm, and serum CKMB, TGO, TGP, LDH, lactate, creatinine, and urea levels were examined. Results: Intravenous administration of recombinant Phα1ß toxin induced analgesia for up to 4 h, with ED50 of 0.02 (0.01-0.03) mg/kg, and reached the maximal effect (Emax = 100% antinociception) at a dose of 0.2 mg/kg. No significant changes were observed in any of the evaluated motor, cardiac or biochemical parameters. Conclusion: Our data suggest that intravenous administration of recombinant Phα1ß may be feasible for drug-induced analgesia, without causing any severe side effects.(AU)


Assuntos
Animais , Camundongos , Ratos , Peptídeos , Injeções Espinhais , Proteínas Recombinantes , Analgesia , Fenômenos Bioquímicos , Preparações Farmacêuticas
7.
Acta sci. vet. (Impr.) ; 48: Pub.1721-Jan. 30, 2020. ilus
Artigo em Português | VETINDEX | ID: biblio-1458244

Resumo

Background: Chinchilla (Chinchilla lanigera) is a small rodent that in recent years has been increasingly used as a laboratory animal by different researchers. Brain irrigation is the object of study by several authors, being chinchilla classifiedas a vertebrobasillary animal, that is, it does not depend on the internal carotid artery to originate its cerebral arterialvascularization. Thus, the objective of this study was to systematize and describe the branches of the rostral, middle andcaudal cerebral arteries that vascularized the paleopallia area of the chinchilla.Materials, Methods & Results: Thirty Chinchilla lanigera brains were used in this study, 17 females and 13 adult malesfrom farms in the municipalities of Viamão and Santa Maria in the state of Rio Grande do Sul, Brazil. The animals wereheparinized, with 5000 IU / animal, and after 30 min were sacrificed with 8 mL / 2.5% sodium thiopental animal, bothintraperitoneally. The thoracic cavity was opened, the cardiac apex sectioned and the aortic arch was cannulated throughthe left ventricle. The arterial system was flushed with 0.9% cooled saline, 100mL / animal and then filled with 603 latexstained red with specific dye. The skin was recessed and a bone window opened in the cranial vault. Thus the pieces werefixed in 20% formaldehyde for seven days and after this period, the brain with a cervical spinal cord segment was removedand ventral schematic drawings of all preparations were prepared. The Veterinary Anatomical Nomina (2017) was usedto name the cerebral arteries and their branches and for the statistical analysis of the results, the percentage calculationwas applied. Brain irrigation in the chinchilla was supplied by the basilar artery, which was formed by anastomosis of theterminal branches of the right and left vertebral arteries, in the most caudal portion of the oblong medulla. The paleopalliaareas corresponded to the olfactory trine, lateral brain fossa, piriform lobe...


Assuntos
Animais , Chinchila/anatomia & histologia , Cérebro/anatomia & histologia , Cérebro/irrigação sanguínea
8.
Acta sci. vet. (Online) ; 48: Pub. 1721, Mar. 21, 2020. ilus
Artigo em Português | VETINDEX | ID: vti-25407

Resumo

Background: Chinchilla (Chinchilla lanigera) is a small rodent that in recent years has been increasingly used as a laboratory animal by different researchers. Brain irrigation is the object of study by several authors, being chinchilla classifiedas a vertebrobasillary animal, that is, it does not depend on the internal carotid artery to originate its cerebral arterialvascularization. Thus, the objective of this study was to systematize and describe the branches of the rostral, middle andcaudal cerebral arteries that vascularized the paleopallia area of the chinchilla.Materials, Methods & Results: Thirty Chinchilla lanigera brains were used in this study, 17 females and 13 adult malesfrom farms in the municipalities of Viamão and Santa Maria in the state of Rio Grande do Sul, Brazil. The animals wereheparinized, with 5000 IU / animal, and after 30 min were sacrificed with 8 mL / 2.5% sodium thiopental animal, bothintraperitoneally. The thoracic cavity was opened, the cardiac apex sectioned and the aortic arch was cannulated throughthe left ventricle. The arterial system was flushed with 0.9% cooled saline, 100mL / animal and then filled with 603 latexstained red with specific dye. The skin was recessed and a bone window opened in the cranial vault. Thus the pieces werefixed in 20% formaldehyde for seven days and after this period, the brain with a cervical spinal cord segment was removedand ventral schematic drawings of all preparations were prepared. The Veterinary Anatomical Nomina (2017) was usedto name the cerebral arteries and their branches and for the statistical analysis of the results, the percentage calculationwas applied. Brain irrigation in the chinchilla was supplied by the basilar artery, which was formed by anastomosis of theterminal branches of the right and left vertebral arteries, in the most caudal portion of the oblong medulla. The paleopalliaareas corresponded to the olfactory trine, lateral brain fossa, piriform lobe...(AU)


Assuntos
Animais , Chinchila/anatomia & histologia , Cérebro/anatomia & histologia , Cérebro/irrigação sanguínea
9.
J. Venom. Anim. Toxins incl. Trop. Dis. ; 26: e20190070, Apr. 17, 2020. tab, graf
Artigo em Inglês | VETINDEX | ID: vti-25951

Resumo

Background: Intrathecal injection of voltage-sensitive calcium channel blocker peptide toxins exerts analgesic effect in several animal models of pain. Upon intrathecal administration, recombinant Phα1β exerts the same analgesic effects as the those of the native toxin. However, from a clinical perspective, the intrathecal administration limits the use of anesthetic drugs in patients. Therefore, this study aimed to investigate the possible antinociceptive effect of intravenous recombinant Phα1β in rat models of neuropathic pain, as well as its side effects on motor, cardiac (heart rate and blood pressure), and biochemical parameters. Methods: Male Wistar rats and male Balb-C mice were used in this study. Giotto Biotech® synthesized the recombinant version of Phα1β using Escherichia coli expression. In rats, neuropathic pain was induced by chronic constriction of the sciatic nerve and paclitaxel-induced acute and chronic pain. Mechanical sensitivity was evaluated using von Frey filaments. A radiotelemeter transmitter (TA11PA-C10; Data Sciences, St. Paul, MN, USA) was placed on the left carotid of mice for investigation of cardiovascular side effects. Locomotor activity data were evaluated using the open-field paradigm, and serum CKMB, TGO, TGP, LDH, lactate, creatinine, and urea levels were examined. Results: Intravenous administration of recombinant Phα1β toxin induced analgesia for up to 4 h, with ED50 of 0.02 (0.01-0.03) mg/kg, and reached the maximal effect (Emax = 100% antinociception) at a dose of 0.2 mg/kg. No significant changes were observed in any of the evaluated motor, cardiac or biochemical parameters. Conclusion: Our data suggest that intravenous administration of recombinant Phα1β may be feasible for drug-induced analgesia, without causing any severe side effects.(AU)


Assuntos
Animais , Masculino , Ratos , Venenos de Aranha/química , Toxinas Biológicas/administração & dosagem , Toxinas Biológicas/efeitos adversos , Analgésicos , Neuropatia Ciática/terapia , Paclitaxel , Ratos Wistar , Camundongos Endogâmicos BALB C , Administração Intravenosa
10.
J. venom. anim. toxins incl. trop. dis ; 26: e20190070, 2020. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1484764

Resumo

Background: Intrathecal injection of voltage-sensitive calcium channel blocker peptide toxins exerts analgesic effect in several animal models of pain. Upon intrathecal administration, recombinant Phα1β exerts the same analgesic effects as the those of the native toxin. However, from a clinical perspective, the intrathecal administration limits the use of anesthetic drugs in patients. Therefore, this study aimed to investigate the possible antinociceptive effect of intravenous recombinant Phα1β in rat models of neuropathic pain, as well as its side effects on motor, cardiac (heart rate and blood pressure), and biochemical parameters. Methods: Male Wistar rats and male Balb-C mice were used in this study. Giotto Biotech® synthesized the recombinant version of Phα1β using Escherichia coli expression. In rats, neuropathic pain was induced by chronic constriction of the sciatic nerve and paclitaxel-induced acute and chronic pain. Mechanical sensitivity was evaluated using von Frey filaments. A radiotelemeter transmitter (TA11PA-C10; Data Sciences, St. Paul, MN, USA) was placed on the left carotid of mice for investigation of cardiovascular side effects. Locomotor activity data were evaluated using the open-field paradigm, and serum CKMB, TGO, TGP, LDH, lactate, creatinine, and urea levels were examined. Results: Intravenous administration of recombinant Phα1β toxin induced analgesia for up to 4 h, with ED50 of 0.02 (0.01-0.03) mg/kg, and reached the maximal effect (Emax = 100% antinociception) at a dose of 0.2 mg/kg. No significant changes were observed in any of the evaluated motor, cardiac or biochemical parameters. Conclusion: Our data suggest that intravenous administration of recombinant Phα1β may be feasible for drug-induced analgesia, without causing any severe side effects.


Assuntos
Masculino , Animais , Ratos , Analgésicos , Neuropatia Ciática/terapia , Paclitaxel , Toxinas Biológicas/administração & dosagem , Toxinas Biológicas/efeitos adversos , Venenos de Aranha/química , Administração Intravenosa , Camundongos Endogâmicos BALB C , Ratos Wistar
11.
Ciênc. Anim. (Impr.) ; 29(4,supl.3): 53-56, 2019.
Artigo em Português | VETINDEX | ID: vti-759372

Resumo

O sistema cardiovascular tem a função de transportar substâncias essenciais à vida. Os vasos sanguíneos conduzem o conteúdo sanguíneo, tanto para a chegada de sangue arterial aos órgãos quanto para saída de sangue venoso. As artérias carótidas comum são originárias do tronco braquiocefálico, sendo o principal vaso responsável pelo aporte sanguíneo dos órgãos da cabeça. Qualquer alteração que prejudique a circulação cerebral pode gerar graves consequências fisiológicas ao animal. A ruptura da artéria carótida pode ser reconhecida como a mais temida das ocorrências na área cirúrgica de cabeça e pescoço, com a perda de sangue excessiva advinda da ruptura de um vaso de calibre e pressão consideráveis, se não for atendido emergencialmente, o animal poderá entrar em um quadro de choque hipovolêmico, agravando o quadro do paciente. Por ser uma problemática não rotineira na clínica cirúrgica de pequenos animais, há poucos registros de casos semelhantes. No caso relatado, o animal apresentava lesão na região cervical, com exposição da veia jugular e ruptura da artéria carótida comum, com presença de hemorragia extrema. O procedimento cirúrgico transcorreu dentro dos parâmetros normais e sem imprevistos. Ao longo do acompanhamento clínico, o animal apresentou um pós cirúrgico estável, sem sequelas neurológicas, seguindo os cuidados com relação aos curativos diários da ferida operatória, continuação do protocolo iniciado no pré-cirúrgico e medicações prescritas para recuperação do volume perdido de hemácias, apresentando uma recuperação positiva.(AU)


The cardiovascular system has the function of transporting essential substances to life. Blood vessels carry the blood content, both for the arrival of arterial blood to the organs and for venous blood output. The common carotid arteries originate from the brachiocephalic trunk, being the main vessel responsible for the blood supply of the head organs. Any alteration that impairs the cerebral circulation can have serious physiological consequences to the animal. Carotid artery rupture can be recognized as the most dreaded occurrence in the head and neck surgical area, with excessive blood loss from a ruptured vessel of considerable caliber and pressure. If left unattended, the animal may enter in a hypovolemic shock, aggravating the patient's condition. As it is a non-routine problem in the small animal surgical clinic, there are few reports of similar cases. In the reported case, the animal had cervical lesion, with exposure of the jugular vein and rupture of the common carotid artery, with the presence of extreme hemorrhage. The surgical procedure was performed within normal parameters and without unforeseen events. During the clinical follow-up, the animal presented a stable postoperative period, without neurological sequelae, following the care regarding the daily wound dressing, continuation of the protocol initiated before the surgery and prescribed medications to recover the lost volume of red blood cells, showing a positive recovery.(AU)


Assuntos
Animais , Cães , Lesões das Artérias Carótidas/veterinária , Doenças do Cão , Ruptura/veterinária
12.
Ciênc. Anim. (Impr.) ; 29(4,supl.3): 53-56, 2019.
Artigo em Português | VETINDEX | ID: biblio-1395279

Resumo

O sistema cardiovascular tem a função de transportar substâncias essenciais à vida. Os vasos sanguíneos conduzem o conteúdo sanguíneo, tanto para a chegada de sangue arterial aos órgãos quanto para saída de sangue venoso. As artérias carótidas comum são originárias do tronco braquiocefálico, sendo o principal vaso responsável pelo aporte sanguíneo dos órgãos da cabeça. Qualquer alteração que prejudique a circulação cerebral pode gerar graves consequências fisiológicas ao animal. A ruptura da artéria carótida pode ser reconhecida como a mais temida das ocorrências na área cirúrgica de cabeça e pescoço com a perda de sangue excessiva advinda da ruptura de um vaso de calibre e pressão consideráveis, se não for atendido emergencialmente, o animal poderá entrar em um quadro de choque hipovolêmico, agravando o quadro do paciente. Por ser uma problemática não rotineira na clínica cirúrgica de pequenos animais, há poucos registros de casos semelhantes. No caso relatado, o animal apresentava lesão na região cervical, com exposição da veia jugular e ruptura da artéria carótida comum, com presença de hemorragia extrema. O procedimento cirúrgico transcorreu dentro dos parâmetros normais e sem imprevistos. Ao longo do acompanhamento clínico, o animal apresentou um póscirúrgico estável, sem sequelas neurológicas, seguindo os cuidados com relação aos curativos diários da ferida operatória, continuação do protocolo iniciado no pré-cirúrgico e medicações prescritas para recuperação do volume perdido de hemácias, apresentando uma recuperação positiva.


The cardiovascular system has the function of transporting essential substances to life. Blood vessels carry the blood content, both for the arrival of arterial blood to the organs and for venous blood output. The common carotid arteries originate from the brachiocephalic trunk, being the main vessel responsible for the blood supply of the head organs. Any alteration that impairs the cerebral circulation can have serious physiological consequences to the animal. Carotid artery rupture can be recognized as the most dreaded occurrence in the head and neck surgical area, with excessive blood loss from a ruptured vessel of considerable caliber and pressure. If left unattended, the animal may enter in a hypovolemic shock, aggravating the patient's condition. As it is a non-routine problem in the small animal surgical clinic, there are few reports of similar cases. In the reported case, the animal had cervical lesion, with exposure of the jugular vein and rupture of the common carotid artery, with the presence of extreme hemorrhage. The surgical procedurewas performed within normal parameters and without unforeseen events. During the clinical follow-up, the animal presented a stable postoperative period, without neurological sequelae, following the care regarding the daily wound dressing, continuation of the protocol initiated before the surgery and prescribed medications to recover the lost volume of red blood cells, showing a positive recovery.


Assuntos
Animais , Cães , Procedimentos Cirúrgicos Operatórios/veterinária , Artérias Carótidas , Doenças do Cão , Cabeça , Pescoço
13.
Acta sci. vet. (Impr.) ; 47: Pub.1631-2019. ilus
Artigo em Português | VETINDEX | ID: biblio-1458029

Resumo

Background: The study was performed on wild boar (Sus scrofa scrofa) wich is a wild ancestor of the domestic pig and is not partof Brazilian fauna. The arterial blood supply of the encephalus has been studied by some researchers, who have systematized thecerebral blood supply from the rostral and caudal epidural rete mirabile and its sources in wild boar until the blood supply of the baseof the brain. The objective was to improve the understanding of the arterial blood supply of the brain, particularly the paleopallium,of the wild boar and to provide a reference for comparative anatomy studies.Materials, Methods & Results: A total of 30 brains were obtained from an officially authorised slaughterhouse and approved byBrazilian Institute of Environment and Natural Renowable Resources. The animals were desensitized, followed by bleending of thejugular veins and common carotid arteries near the entrance of the thorax, according to the slaughter procedure. Finally, the animalswere decapitated at the level of axis vertebra. The cerebral arterial system of each animal was rinsed (cooled saline containing 2500IU of heparin) and drained by the jugular veins, and vessels were filled with latex 603 stained with specific red dye. The heads weresubmerged for one hour in running water immersed in 20% formaldehyde for fixation; the brains were removed along with a cervicalsegment of the spinal cord. The duramater was removed, and the arteries were dissected. Schematic drawings of the ventral view ofthe all preparations were made using magnifying glasses and photographic records. The Nomina Anatomica Veterinaria was usedto named the cerebral arteries and their branches, and calculation of pecentages was applied in the statistical analysis. The cerebralcarotid artery originating from the rostral epidural rete mirabile emitted a rostral branch and a caudal branch on the side of the hypophysis gland...


Assuntos
Animais , Artérias Cerebrais/anatomia & histologia , Cérebro/anatomia & histologia , Cérebro/irrigação sanguínea , Sus scrofa/anatomia & histologia
14.
Acta sci. vet. (Online) ; 47: Pub. 1631, 2019. ilus
Artigo em Português | VETINDEX | ID: vti-18479

Resumo

Background: The study was performed on wild boar (Sus scrofa scrofa) wich is a wild ancestor of the domestic pig and is not partof Brazilian fauna. The arterial blood supply of the encephalus has been studied by some researchers, who have systematized thecerebral blood supply from the rostral and caudal epidural rete mirabile and its sources in wild boar until the blood supply of the baseof the brain. The objective was to improve the understanding of the arterial blood supply of the brain, particularly the paleopallium,of the wild boar and to provide a reference for comparative anatomy studies.Materials, Methods & Results: A total of 30 brains were obtained from an officially authorised slaughterhouse and approved byBrazilian Institute of Environment and Natural Renowable Resources. The animals were desensitized, followed by bleending of thejugular veins and common carotid arteries near the entrance of the thorax, according to the slaughter procedure. Finally, the animalswere decapitated at the level of axis vertebra. The cerebral arterial system of each animal was rinsed (cooled saline containing 2500IU of heparin) and drained by the jugular veins, and vessels were filled with latex 603 stained with specific red dye. The heads weresubmerged for one hour in running water immersed in 20% formaldehyde for fixation; the brains were removed along with a cervicalsegment of the spinal cord. The duramater was removed, and the arteries were dissected. Schematic drawings of the ventral view ofthe all preparations were made using magnifying glasses and photographic records. The Nomina Anatomica Veterinaria was usedto named the cerebral arteries and their branches, and calculation of pecentages was applied in the statistical analysis. The cerebralcarotid artery originating from the rostral epidural rete mirabile emitted a rostral branch and a caudal branch on the side of the hypophysis gland...(AU)


Assuntos
Animais , Sus scrofa/anatomia & histologia , Cérebro/irrigação sanguínea , Cérebro/anatomia & histologia , Artérias Cerebrais/anatomia & histologia
15.
Acta sci. vet. (Impr.) ; 46: Pub.1609-2018. tab, ilus
Artigo em Português | VETINDEX | ID: biblio-1457897

Resumo

Background: Gerbils (Meriones unguiculatus) are rodents belonging to the Muridae family. Recently, breeding of this species as pets has increased significantly. Animal models are being investigated to study diseases related to the human aortic arch. Despite the importance of the aortic arch in maintaining homeostasis, there is limited data available regarding its morphology in gerbils. This study was performed with the objective of describing the collateral branches of the aortic arch in this animal to establish a standard model and thus contribute to future research on cardiovascular diseases in humans.Materials, Methods & Results: This study used 20 male specimens from previous studies that were frozen and stored at the Laboratory of Veterinary Anatomy of the Federal Rural University of the Semi-Arid Region. After thawing the animals, the thoracic cavity was opened for aortic cannulation. The vascular system was washed using saline solution and Neoprene latex stained with red pigment was injected. Subsequently, the animals were fixed in 10% formaldehyde and were dissected and analyzed 72 h later. The arrangement of the collateral branches of the aortic arch in gerbils was analyzed in all animals. The brachiocephalic trunk, the left common carotid, and the left subclavian artery were observed to originate as collateral branches. The brachiocephalic trunk bifurcated into the right common carotid and the right subclavian arteries. The right and the left subclavian arteries branched into the vertebral artery, the internal thoracic artery, the superficial cervical artery, the costocervical trunk, and the axillary artery.[...]


Assuntos
Masculino , Animais , Aorta Torácica/anatomia & histologia , Experimentação Animal , Hemodinâmica , Sistema Cardiovascular , Gerbillinae
16.
Acta sci. vet. (Online) ; 46: Pub. 1609, 2018. tab, ilus
Artigo em Português | VETINDEX | ID: vti-735405

Resumo

Background: Gerbils (Meriones unguiculatus) are rodents belonging to the Muridae family. Recently, breeding of this species as pets has increased significantly. Animal models are being investigated to study diseases related to the human aortic arch. Despite the importance of the aortic arch in maintaining homeostasis, there is limited data available regarding its morphology in gerbils. This study was performed with the objective of describing the collateral branches of the aortic arch in this animal to establish a standard model and thus contribute to future research on cardiovascular diseases in humans.Materials, Methods & Results: This study used 20 male specimens from previous studies that were frozen and stored at the Laboratory of Veterinary Anatomy of the Federal Rural University of the Semi-Arid Region. After thawing the animals, the thoracic cavity was opened for aortic cannulation. The vascular system was washed using saline solution and Neoprene latex stained with red pigment was injected. Subsequently, the animals were fixed in 10% formaldehyde and were dissected and analyzed 72 h later. The arrangement of the collateral branches of the aortic arch in gerbils was analyzed in all animals. The brachiocephalic trunk, the left common carotid, and the left subclavian artery were observed to originate as collateral branches. The brachiocephalic trunk bifurcated into the right common carotid and the right subclavian arteries. The right and the left subclavian arteries branched into the vertebral artery, the internal thoracic artery, the superficial cervical artery, the costocervical trunk, and the axillary artery.[...](AU)


Assuntos
Animais , Masculino , Aorta Torácica/anatomia & histologia , Sistema Cardiovascular , Hemodinâmica , Experimentação Animal , Gerbillinae
17.
Acta sci. vet. (Impr.) ; 46: 1-8, 2018. ilus
Artigo em Português | VETINDEX | ID: biblio-1457836

Resumo

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,[...]


Assuntos
Animais , Artérias Cerebrais/anatomia & histologia , Cérebro/irrigação sanguínea , Círculo Arterial do Cérebro/anatomia & histologia , Reiformes/anatomia & histologia , Veias Cerebrais/anatomia & histologia
18.
Acta sci. vet. (Online) ; 46: 1-8, 2018. ilus
Artigo em Português | VETINDEX | ID: vti-728667

Resumo

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)


Assuntos
Animais , Reiformes/anatomia & histologia , Artérias Cerebrais/anatomia & histologia , Círculo Arterial do Cérebro/anatomia & histologia , Veias Cerebrais/anatomia & histologia , Cérebro/irrigação sanguínea
19.
Acta sci. vet. (Impr.) ; 46: Pub.1614-2018. ilus
Artigo em Inglês | VETINDEX | ID: biblio-1457904

Resumo

Background: The investigation on the cardiocirculatory system in chinchilla has become increasingly important due to the use of the species in experimental medicine (toxicology, pathology, parasitology etc.). Even though initially this species was regarded with a strict economic interest, in the last period, chinchillas have become an increasingly-encountered patient in veterinary clinics and hospitals. Another aspect is the use of the species in medical research, as experimental model or in parasitology. The present study tackles a combined anatomical and radiological (angiographical) study to accurately describe the vascular anatomy of the initial part of the aortic arch (Arcus aortae).Materials, Methods & Results: The anatomical distribution of collaterals detached from arcus aorticus (brachiocephalic trunk and subclavian arteries) are highlighted in this paper. To do that, the classical stratigraphic anatomical investigation, followed by the radiological study with the help of the contrast substance injected into the vascular bed were used in combination. Several Chinchilla lanigera female carcasses, obtained from a private commercial farming unit in Cluj county, Romania were used for this study. Ten carcasses were used for the anatomical study, being injected into the vascular bed with a mixture of latex and acrylic dye, fixated into formaldehyde 5% and later dissected, while the other ten carcasses were injected at the level of the aortic arch with Visipaque 320 contrast substance and subjected to the angiographical procedure.The anatomical investigation was carried after an initial 5 day-fixation period, while the angiographic procedure was initiated using the TEMCO Grx-01 device and the Veterinary Digital Imaging System® as digital imaging processing software. This combined study shows the differential mode of emergence of the subclavian and carotid arteries in this species.[...]


Assuntos
Feminino , Animais , Aorta Torácica/anatomia & histologia , Chinchila , Tronco Braquiocefálico/anatomia & histologia , Angiografia/métodos , Angiografia/veterinária
20.
Acta sci. vet. (Online) ; 46: Pub. 1614, 2018. ilus
Artigo em Inglês | VETINDEX | ID: vti-738785

Resumo

Background: The investigation on the cardiocirculatory system in chinchilla has become increasingly important due to the use of the species in experimental medicine (toxicology, pathology, parasitology etc.). Even though initially this species was regarded with a strict economic interest, in the last period, chinchillas have become an increasingly-encountered patient in veterinary clinics and hospitals. Another aspect is the use of the species in medical research, as experimental model or in parasitology. The present study tackles a combined anatomical and radiological (angiographical) study to accurately describe the vascular anatomy of the initial part of the aortic arch (Arcus aortae).Materials, Methods & Results: The anatomical distribution of collaterals detached from arcus aorticus (brachiocephalic trunk and subclavian arteries) are highlighted in this paper. To do that, the classical stratigraphic anatomical investigation, followed by the radiological study with the help of the contrast substance injected into the vascular bed were used in combination. Several Chinchilla lanigera female carcasses, obtained from a private commercial farming unit in Cluj county, Romania were used for this study. Ten carcasses were used for the anatomical study, being injected into the vascular bed with a mixture of latex and acrylic dye, fixated into formaldehyde 5% and later dissected, while the other ten carcasses were injected at the level of the aortic arch with Visipaque 320 contrast substance and subjected to the angiographical procedure.The anatomical investigation was carried after an initial 5 day-fixation period, while the angiographic procedure was initiated using the TEMCO Grx-01 device and the Veterinary Digital Imaging System® as digital imaging processing software. This combined study shows the differential mode of emergence of the subclavian and carotid arteries in this species.[...](AU)


Assuntos
Animais , Feminino , Chinchila , Aorta Torácica/anatomia & histologia , Tronco Braquiocefálico/anatomia & histologia , Angiografia/métodos , Angiografia/veterinária
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