The influence of paraventricular nucleus of the hypothalamus soluble guanylate cyclase on autonomic and neuroendocrine responses to acute restraint stress in rats

Autor(es)

Busnardo, Cristiane ; Crestani, Carlos C. ; Fassini, Aline ; Scarambone, Bianca M. ; Packard, Benjamin A. ; Resstel, Leonardo B. M. ; Herman, James P. ; Correa, Fernando M. A.

• Tipo de documento: Artigo Científico
• Fonte: European Journal of Neuroscience; v. N/A, p. 12-pg., 2024-09-05.

Resumo

The paraventricular nucleus of the hypothalamus (PVN) regulates physiological and behavioural responses evoked by stressful stimuli, but the local neurochemical and signalling mechanisms involved are not completely understood. The soluble guanylate cyclase (sGC) within the PVN is implicated in autonomic and cardiovascular control in rodents under resting conditions. However, the involvement of PVN sGC-mediated signalling in stress responses is unknown. Therefore, we investigated the role of sGC within the PVN in cardiovascular, autonomic, neuroendocrine, and local neuronal responses to acute restraint stress in rats. Bilateral microinjection of the selective sGC inhibitor ODQ (1 nmol/100 nl) into the PVN reduced both the increased arterial pressure and the drop in cutaneous tail temperature evoked by restraint stress, while the tachycardia was enhanced. Intra-PVN injection of ODQ did not alter the number of Fos-immunoreactive neurons in either the dorsal cap parvocellular (PaDC), ventromedial (PaV), medial parvocellular (PaMP), or lateral magnocelllular (PaLM) portions of the PVN following acute restraint stress. Local microinjection of ODQ into the PVN did not affect the restraint-induced increases in plasma corticosterone concentration. Taken together, these findings suggest that sGC-mediated signalling in the PVN plays a key role in acute stress-induced pressor responses and sympathetically mediated cutaneous vasoconstriction, whereas the tachycardiac response is inhibited. Absence of an effect of ODQ on corticosterone and PVN neuronal activation in and the PaV and PaMP suggests that PVN sGC is not involved in restraint-evoked hypothalamus-pituitary-adrenal (HPA) axis activation and further indicates that autonomic and neuroendocrine responses are dissociable at the level of the PVN. image (AU)

• Processo FAPESP: 13/00249-9 - Envolvimento da neurotransmissão opioidérgica da amígdala medial na mediação das respostas autonômicas e hormonais causadas pelo estresse de restrição em ratos
• Beneficiário: Aline Fassini
• Modalidade de apoio: Bolsas no Brasil - Doutorado
• Processo FAPESP: 21/04572-5 - Estudo do envolvimento da neurotransmissão hipocampal nos mecanismos centrais das respostas comportamentais ao estresse crônico repetido
• Beneficiário: Luana Omena Giatti
• Modalidade de apoio: Bolsas no Brasil - Iniciação Científica
• Processo FAPESP: 21/00148-4 - Estudo genético da neurotransmissão glutamatérgica no hipocampo nos mecanismos centrais de adaptação das respostas neuroendócrina, cardiovascular e comportamental ao estresse crônico repetido e da neuroinflamação induzida pelo estresse
• Beneficiário: Cristiane Busnardo Santiago
• Modalidade de apoio: Bolsas no Brasil - Jovens Pesquisadores