Selective denervation of the aortic and carotid baroreceptors in rats

Autor(es)

Castania, Jaci A. ^[1] ; Katayama, Pedro L. ^[1] ; Brognara, Fernanda ^[1] ; Moraes, Davi J. A. ^[1] ; Sabino, Joao Paulo J. ^[2] ; Salgado, Helio C. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Ribeirao Preto Med Sch, Dept Physiol, Ave Bandeirantes 3900, BR-14049900 Ribeirao Preto, SP - Brazil

^[2] Univ Fed Piaui, Dept Biophys & Physiol, Teresina, Piaui - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Experimental Physiology; v. 104, n. 9, p. 1335-1342, SEP 2019.
• Citações Web of Science: 0

Resumo

Studies have demonstrated that the traditional surgical approach for sino-aortic denervation in rats leads to simultaneous carotid baroreceptor and chemoreceptor deactivation. The present study reports a new surgical approach to denervate the aortic and the carotid baroreceptors selectively, keeping the carotid bodies (peripheral chemoreceptors) intact. Wistar rats were subjected to specific aortic and carotid baroreceptor denervation (BAROS-X) or sham surgery (SHAM). Baroreflex activation was achieved by i.v. administration of phenylephrine, whereas peripheral chemoreflex activation was produced by i.v. administration of potassium cyanide. The SHAM and BAROS-X rats displayed significant hypertensive responses to phenylephrine administration. However, the reflex bradycardia following the hypertensive response caused by phenylephrine was remarkable in SHAM, but not significant in the BAROS-X animals, confirming the efficacy of the surgical procedure to abolish the baroreflex. In addition, the baroreflex activation elicited by phenylephrine increased carotid sinus nerve activity only in SHAM, but not in the BAROS-X animals, providing support to the notion that the baroreceptor afferents were absent. Instead, the classical peripheral chemoreflex hypertensive and bradycardic responses to potassium cyanide were similar in both groups, suggesting that the carotid body chemoreceptors were preserved after BAROS-X. In summary, we describe a new surgical approach in which only the baroreceptors are eliminated, while the carotid chemoreceptors are preserved. Therefore, it is understood that this procedure is potentially a useful tool for examining the relative roles of the arterial baroreceptors versus the chemoreceptors in several pathophysiological conditions, for instance, arterial hypertension and heart failure. (AU)

• Processo FAPESP: 17/05163-6 - Papel do sistema nervoso autônomo parassimpático e simpático na modulação da sepse em ratos não anestesiados
• Beneficiário: Fernanda Brognara Penteado Dias
• Modalidade de apoio: Bolsas no Brasil - Doutorado Direto
• Processo FAPESP: 13/10484-5 - Caracterização eletrofisiológica e molecular dos neurônios envolvidos na geração do ritmo e do padrão respiratório de ratos durante o desenvolvimento pós-natal
• Beneficiário: Davi José de Almeida Moraes
• Modalidade de apoio: Auxílio à Pesquisa - Jovens Pesquisadores
• Processo FAPESP: 13/20549-7 - Avanços na regulação cardiocirculatória em condições fisiológica e fisiopatológica
• Beneficiário: Helio Cesar Salgado
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 15/18511-7 - Papel dos quimiorreceptores carotídeos nas respostas hemodinâmicas e ventilatórias à estimulação elétrica do seio carotídeo, e efeitos da sua inibição crônica no desenvolvimento da hipertensão arterial em ratos com hipertensão espontânea (SHR)
• Beneficiário: Pedro Lourenço Katayama
• Modalidade de apoio: Bolsas no Brasil - Doutorado Direto