Possible involvement of nitric oxide in acetylcholine-induced increase of intracellular Ca2+ concentration and catecholamine release in bovine adrenal chromaffin cells.
The role of nitric oxide (NO) in neurotransmitter release was studied using bovine adrenal medullary chromaffin cells. L-Arginine and sodium nitroprusside (SNP) slightly increased the intracellular free calcium concentration ([Ca2+]i), and the effects of the agents were dependent on the presence of the extracellular Ca2+ ([Ca2+]o), but were not blocked by verapamil (30 microM) or diltiazem (30 microM). SNP enhanced the acetylcholine (ACh)-induced rise in [Ca2+]i in the presence but not in the absence of [Ca2+]o. The effects of L-arginine but not those of SNP were inhibited by N omega-nitro-L-arginine (L-NNA). L-NNA significantly reduced the ACh-induced rise in [Ca2+]i and catecholamine (CA) release, and the reduction was restored by L-arginine but not by D-arginine. These results suggest a possible involvement of NO in ACh-induced [Ca2+]i rise and CA release in bovine adrenal chromaffin cells.
Uchiyama
Y
Y
Department of Pharmacology, Hiroshima University School of Dentistry, Japan.
Morita
K
K
Kitayama
S
S
Suemitsu
T
T
Minami
N
N
Miyasako
T
T
Dohi
T
T
D000109:Acetylcholine / Q000494:pharmacology*; D000818:Animals; D001120:Arginine / Q000031:analogs & derivatives / Q000037:antagonists & inhibitors / Q000494:pharmacology; D002118:Calcium / Q000378:metabolism*; D002395:Catecholamines / Q000378:metabolism*; D002417:Cattle; D002478:Cells, Cultured; D002838:Chromaffin System / Q000187:drug effects / Q000378:metabolism*; D009569:Nitric Oxide / Q000502:physiology*; D019335:Nitroarginine; D009599:Nitroprusside / Q000494:pharmacology
D002395:Catecholamines; D009599:Nitroprusside; D019335:Nitroarginine; D009569:Nitric Oxide; D001120:Arginine; D000109:Acetylcholine; D002118:Calcium