Depletion of C1 neurons attenuates the salt-induced hypertension in unanesthetized rats

Autor(es)

Ribeiro, Natalia ^[1] ; Martins Sa, Renato W. ^[1] ; Antunes, Vagner R. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Inst Biomed Sci, Dept Physiol & Biophys, Av Prof Lineu Prestes 1524, BR-05508900 Sao Paulo, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Brain Research; v. 1748, DEC 1 2020.
• Citações Web of Science: 0

Resumo

High salt intake is able to evoke neuroendocrine and autonomic responses that include vasopressin release and sympathoexcitation resulting in increasing in the arterial blood pressure (BP). The C1 neurons are a specific population of catecholaminergic neurons located in the RVLM region and they control BP under homeostatic imbalance. Thus, here we hypothesized that the ablation of C1 neurons mitigate the high blood pressure induced by high-salt intake. To test this hypothesis, we injected anti-D beta H-SAP saporin at the RVLM and monitored the BP in unanesthetized animals exposed to high salt intake of 2% NaCl solution for 7 days. The injection of anti-D beta H-SAP into the RVLM depleted 80% of tyrosine hydroxylase-positive neurons (TH+ neurons) in the C1, 38% in the A5, and no significant reduction in the A1 region, when compared to control group (saline as vehicle). High salt intake elicited a significant increase in BP in the control group, while in the anti-D beta H-SAP group the depletion of TH+ neurons prevents the salt-induced hypertension. Moreover, the low frequency component of systolic BP and pulse interval were increased by high-salt intake in control animals but not in anti-D beta H-SAP group, which indirectly suggests that the increase in the BP is mediated by increase in sympathetic activity. In conclusion, our data show that hypertension induced by high-salt intake is dependent on C1 neurons. (AU)

• Processo FAPESP: 16/21991-3 - Hipertensão secundária à alta ingestão de sal: estudo da sinalização purinérgica em células neuronais do hipotálamo e sua influência na atividade do sistema nervoso autônomo e pressão arterial
• Beneficiário: Vagner Roberto Antunes
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 13/06206-0 - Estudo da expressão gênica de neuropeptídeos e mediadores inflamatórios em núcleos do eixo hipotálamo-tronco cerebral envolvidos no controle neural da pressão arterial de animais submetidos a dieta obesogênica
• Beneficiário: Vagner Roberto Antunes
• Modalidade de apoio: Auxílio à Pesquisa - Regular