pH dependence of pepsinogen and acid secretion in isolated gastric glands.
pH dependence of pepsinogen and acid secretion in isolated gastric glands.
复制标题
离体胃腺中胃蛋白酶原和酸分泌的 pH 依赖性。
DOI：
10.1152/ajpgi.1983.245.6.g730
复制
发表时间：
1983
期刊：
影响因子：
--
通讯作者：
Hersey,SJ
中科院分区：
文献类型：
--
作者：
Norris,SH;Hersey,SJ
用家兔离体胃腺研究胃蛋白酶原和胃酸分泌对腺外pH的依赖性。pH从8.0变化到6.7时，胃蛋白酶原对异丙肾上腺素、卡巴胆碱、八肽胆囊收缩素、Boots'分泌素和高渗的反应略有增加，但对8-溴腺苷3'，5 '-环一磷酸（8BrcAMP）、8-溴肌苷3'，5 '-环状单磷酸（8BrcIMP）和毛喉素。pH值对8 BrcAMP、8 BrcIMP和毛喉素反应的类似影响反映了其拟议作用机制的共同性。得出的结论是，降低腺外pH值间接引起cAMP依赖性蛋白激酶或cAMP依赖性调节胃蛋白酶原分泌的后续步骤的活性增加。当pH从8.0变化到6.7时，8BrcAMP刺激的酸分泌也增加，并提出了类似的解释。然而，组胺刺激的酸分泌和腺苷酸环化酶活性显着下降，pH值降低超过这个范围。有人建议，cAMP是速率限制组胺刺激和pH值对组胺刺激的酸分泌的影响可以归因于pH值对腺苷酸环化酶活性的影响。
Rabbit isolated gastric glands were used to investigate the dependence of pepsinogen and acid secretions on extraglandular pH. Changing pH from 8.0 to 6.7 caused small increases in pepsinogen secretory responses to isoproterenol, carbachol, cholecystokinin octapeptide, Boots' secretin, and hyperosmolarity but caused large increases in responses to 8-bromoadenosine 3',5'-cyclic monophosphate (8BrcAMP), 8-bromoinosine 3',5'-cyclic monophosphate (8BrcIMP), and forskolin. The similar effect of pH on responses to 8BrcAMP, 8BrcIMP, and forskolin was suggested to reflect a commonality in their proposed mechanisms of action. It was concluded that reducing extraglandular pH indirectly caused an increase in activity of cAMP-dependent protein kinase or of a subsequent step in cAMP-dependent regulation of pepsinogen secretion. 8BrcAMP-stimulated acid secretion also increased as pH was changed from 8.0 to 6.7, and a similar explanation of the effect was suggested. However, histamine-stimulated acid secretion and adenyl cyclase activity decreased markedly as pH was lowered over this range. It was suggested that cAMP was rate limiting for stimulation by histamine and that the effect of pH on histamine-stimulated acid secretion could be attributed to an effect of pH on adenyl cyclase activity.