Thompson W J, Chang L K, Jacobson E D
Gastroenterology. 1977 Feb;72(2):244-50.
Prostaglandin E1, epinephrine, secretin, and glucagon are known inhibitors of gastric acid secretion, and each agent stimulated mucosal membrane (600 X g pellet) adenylyl cyclase activity from the corpus of the rat stomach. This adenylyl cyclase activity was also stimulated by 5'-guanylyl-imidodiphosphate and sodium fluoride but not by guanosine-5'-triphosphate. By contrast, the gastric acid secretagogues, pentagastrin, histamine, and carbachol, had no effect on basal or prostaglandin E1-stimulated mucosal adenylyl cyclase activity. Most of the sodium fluoride- and hormone-stimulated adenylyl cyclase of the corpus mucosa was contained in the 600 X g membrane fraction. The enzyme exhibited Michaelis-Menten kinetics with respect to the concentration of ATP, with an apparent Km of 0.25 mM. Histamine did not stimulate rat mucosal adenylyl cyclase activity under a variety of conditions, but did stimulate the same enzyme in guinea pig gastric fundic mucosa, an enzyme also activated by prostaglandin E1. These studies do not support the hypothesis that cyclic AMP mediates the actions of gastric acid secretagogues on the parietal cell in the rat.
前列腺素E1、肾上腺素、促胰液素和胰高血糖素是已知的胃酸分泌抑制剂，并且每种药物都能刺激大鼠胃体黏膜膜（600×g沉淀）的腺苷酸环化酶活性。这种腺苷酸环化酶活性也受到5'-鸟苷酰亚胺二磷酸和氟化钠的刺激，但不受鸟苷-5'-三磷酸的刺激。相比之下，胃酸分泌促进剂五肽胃泌素、组胺和卡巴胆碱对基础或前列腺素E1刺激的黏膜腺苷酸环化酶活性没有影响。胃体黏膜中大部分氟化钠和激素刺激的腺苷酸环化酶存在于600×g膜组分中。该酶对ATP浓度表现出米氏动力学，表观Km为0.25 mM。在各种条件下，组胺都不会刺激大鼠黏膜腺苷酸环化酶活性，但会刺激豚鼠胃底黏膜中的同一种酶，该酶也可被前列腺素E1激活。这些研究不支持环磷酸腺苷介导胃酸分泌促进剂对大鼠壁细胞作用的假说。
