Muscarinic cholinergic inhibition of cyclic AMP formation and adrenocorticotropin secretion in mouse pituitary tumor cells |
| |
| Authors: | S Heisler L Larose J Morisset |
| |
| Institution: | 1. Unité de Biorégulation cellulaire et moléculaire, Centre hospitalier de l''Université Laval, Sainte-Foy, Québec G1V 4G2 Canada;2. Departement de Pharmacologie, Université Laval, Sainte-Foy, Québec G1V 4G2 Canada;3. Centre de Recherche sur les Mécanismes de sécrétion, Département de Biologie, Faculté de Sciences, Université de Sherbrooke, Sherbrooke, Québec J1K 2R1 Canada |
| |
| Abstract: | Cholinergic muscarinic receptors were identified in AtT-20/D16-16 (AtT-20) cell membranes by receptor binding techniques and the effect of carbachol on basal and stimulated cyclic AMP formation and ACTH release was investigated. Carbachol markedly decreased the stimulatory effect of the adenylate cyclase activator, forskolin, on both cyclic AMP formation and ACTH secretion. Carbachol also reduced forskolin-stimulated adenylate cyclase activity. The stimulatory effects of (-) isoproterenol on cyclic nucleotide formation and ACTH secretion were also blocked by carbachol. The inhibitory effects of carbachol on (-) isoproterenol-stimulated cyclic AMP synthesis and ACTH secretion were reversed by the muscarinic antagonist, atropine, and not by the nicotinic antagonist, gallamine. These data suggest that in AtT-20 cells, inhibition of ACTH secretion may be regulated by activation of muscarinic receptors coupled negatively to adenylate cyclase. |
| |
| Keywords: | ACTH adrenocorticotropin hormone CRF corticotropin releasing factor IBMX 3-isobutyl-1-methylxanthine QNB quinuclidinyl benzilate SEM standard error of the mean SRIF somatostatin VIP vasoactive intestinal peptide |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
