Thompson W J, Chang L K, Rosenfeld G C, Jacobson E D
Gastroenterology. 1977 Feb;72(2):251-4.
Prostaglandin (PG) E1, E2, A1, and A2 stimulated rat gastric corpus mucosal membrane adenylyl cyclase activity. PGE1 (Kalpha congruent to 8 muM) affected the maximum velocity but not the affinity of the enzyme for ATP and maximum PGE1 activation was not affected by histamine H1 or H2 receptor antagonists. 5'-Guanylyl-diphosphoimide (Gpp(NH)p), but not GTP, stimulated both the basal and PGE1-stimulated adenylyl cyclase activities, although the percentage stimulation by maximal PGE was the same with or without Gpp(NH)p. NaF stimulation was also additive to that of PGE1. Secretin also stimulated gastric mucosal adenylyl cyclase activity (Kalpha congruent to 30 nM). Maximal secretin activation was not additive to that of PGE1, suggesting a coupling to the same adenylyl cyclase catalytic site. These studies suggest that mucosal membranes may contain beta-adrenergic receptors. The adenylyl cyclase activating agents used in this study, PGE1, secretin, and the catecholamines, are all known inhibitors of gastric acid secretion, suggesting a possible involvement of cyclic AMP in the inhibition of acid secretion in the rat stomach.
前列腺素（PG）E1、E2、A1和A2刺激大鼠胃体黏膜膜腺苷酸环化酶活性。PGE1（Ka约为8μM）影响酶对ATP的最大反应速度但不影响亲和力，组胺H1或H2受体拮抗剂不影响PGE1的最大激活作用。5'-鸟苷二磷酸亚胺（Gpp(NH)p）而非GTP刺激基础和PGE1刺激的腺苷酸环化酶活性，尽管有无Gpp(NH)p时PGE最大刺激百分比相同。NaF刺激与PGE1刺激也具有相加性。促胰液素也刺激胃黏膜腺苷酸环化酶活性（Ka约为30 nM）。促胰液素的最大激活作用与PGE1的最大激活作用不具有相加性，提示其与同一腺苷酸环化酶催化位点偶联。这些研究提示黏膜膜可能含有β-肾上腺素能受体。本研究中使用的腺苷酸环化酶激活剂PGE1、促胰液素和儿茶酚胺均为已知的胃酸分泌抑制剂，提示环磷酸腺苷可能参与大鼠胃中酸分泌的抑制。
