Angiotensin II mediates catecholamine and neuropeptide Y secretion in human adrenal chromaffin cells through the AT1 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-AT(2) agonist, T(2)-(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 Ca(2+) concentration ([Ca(2+)](i)). The selective AT(1)-receptor antagonist Candesartan blocked [Ca(2+)](i) increase by Ang II, while T(2)-(Ang II 4-8)(2) was ineffective. These findings demonstrate that AT(1) stimulation induces catecholamine secretion from human adrenal chromaffin cells probably by raising cytosolic calcium.
Cavadas
Claudia
C
Division of Hypertension and Vascular Medicine, Centre Hospitalier Universitaire Vaudois, 1011 Lausanne, Switzerland.
Grand
Daniela
D
Mosimann
François
F
Cotrim
Maria Dulce
MD
Fontes Ribeiro
Carlos Alberto
CA
Brunner
Hans R
HR
Grouzmann
Eric
E
D000311:Adrenal Glands / Q000166:cytology; D000804:Angiotensin II / Q000378:metabolism / Q000494:pharmacology*; D047228:Angiotensin II Type 1 Receptor Blockers; D002118:Calcium / Q000737:chemistry / Q000378:metabolism; D002478:Cells, Cultured; D019439:Chromaffin Cells / Q000187:drug effects / Q000378:metabolism*; D004837:Epinephrine / Q000378:metabolism*; D006801:Humans; D009478:Neuropeptide Y / Q000378:metabolism*; D009638:Norepinephrine / Q000378:metabolism*; D044140:Receptor, Angiotensin, Type 1 / Q000819:agonists / Q000378:metabolism*; D015398:Signal Transduction
D047228:Angiotensin II Type 1 Receptor Blockers; D009478:Neuropeptide Y; D044140:Receptor, Angiotensin, Type 1; D000804:Angiotensin II; D002118:Calcium; D009638:Norepinephrine; D004837:Epinephrine