Angiotensin II mediates catecholamine and neuropeptide Y secretion in human adrenal chromaffin cells through the AT1 receptor

• Main Author: Cavadas, Cláudia
• Publication Date: 2003
• Other Authors: Grand, Daniela, Mosimann, François, Cotrim, Maria Dulce, Ribeiro, Carlos Alberto Fontes, Brunner, Hans R., Grouzmann, Eric
• Format: Article
• Language: eng
• Source: Repositórios Científicos de Acesso Aberto de Portugal (RCAAP)
• Download full: https://hdl.handle.net/10316/5782; https://doi.org/10.1016/s0167-0115(02)00253-7; https://doi.org/10.1016/S0167-0115(02)00253-7
• topic: Human adrenal chromaffin cells; Catecholamines; Neuropeptide Y; Angiotensin II; AT1 receptor; AT2 receptor

The aim of the present work was to study the effect of angiotensin II (Ang II) on catecholamines and neuropeptide Y (NPY) release in primary cultures of human adrenal chromaffin cells. Ang II stimulates norepinephrine (NE), epinephrine (EP) and NPY release from perifused chromaffin cells by 3-, 2- and 12-fold, respectively. The NPY release is more sustained than that of catecholamines. We found that the receptor-AT2 agonist, T2-(Ang II 4-8)2 has no effect on NE, EP and NPY release from chromaffin cells. We further showed that Ang II increases intracellular Ca2+ concentration ([Ca2+]i). The selective AT1-receptor antagonist Candesartan blocked [Ca2+]i increase by Ang II, while T2-(Ang II 4-8)2 was ineffective. These findings demonstrate that AT1 stimulation induces catecholamine secretion from human adrenal chromaffin cells probably by raising cytosolic calcium.