Collen M J, Sutliff V E, Pan G Z, Gardner J D
Am J Physiol. 1982 Apr;242(4):G423-8. doi: 10.1152/ajpgi.1982.242.4.G423.
In dispersed acini from rat pancreas, secretagogues that act through or mimic the action of AMP [vasoactive intestinal peptide (VIP), secretin, or 8-bromo-AMP] caused a twofold increase in amylase secretion. Secretagogues that mobilize cellular calcium (carbamylcholine, C-terminal octapeptide of cholecystokinin, bombesin, or A23187) caused a sevenfold augmentation of the actions of VIP, secretin, or 8-bromo-cAMP on enzyme secretion. Carbamylcholine and the C-terminal octapeptide of cholecystokinin also augmented the action of VIP on amylase secretion from mouse pancreatic acini. Secretagogues that mobilize cellular calcium did not alter binding of 125I-VIP, cellular cAMP, or the increase in cellular cAMP caused by VIP or secretin. Similarly, secretagogues that increase cellular cAMP did not alter 45Ca outflux or the increase in 45Ca outflux caused by carbamylcholine, C-terminal octapeptide of cholecystokinin, bombesin, or A23187. These results indicate that in dispersed acini from rat pancreas there is postreceptor modulation of the actions of VIP and secretin on enzyme secretion by secretagogues that mobilize cellular calcium and that this modulation is a major determinant of the magnitude of the effect of VIP and secretin on enzyme secretion. This modulation, in turn, reflects the ability of cellular calcium, mobilized from intracellular stores, to amplify the action of cellular cAMP on the enzyme secretory process.
在大鼠胰腺的分散腺泡中，通过AMP发挥作用或模拟其作用的促分泌剂（血管活性肠肽（VIP）、促胰液素或8-溴-AMP）可使淀粉酶分泌增加两倍。动员细胞内钙的促分泌剂（氨甲酰胆碱、胆囊收缩素C端八肽、蛙皮素或A23187）可使VIP、促胰液素或8-溴-cAMP对酶分泌的作用增强7倍。氨甲酰胆碱和胆囊收缩素C端八肽也增强了VIP对小鼠胰腺腺泡淀粉酶分泌的作用。动员细胞内钙的促分泌剂不会改变125I-VIP的结合、细胞内cAMP水平，也不会改变由VIP或促胰液素引起的细胞内cAMP的增加。同样，增加细胞内cAMP的促分泌剂不会改变45Ca外流或由氨甲酰胆碱、胆囊收缩素C端八肽、蛙皮素或A23187引起的45Ca外流的增加。这些结果表明，在大鼠胰腺的分散腺泡中，动员细胞内钙的促分泌剂对VIP和促胰液素的酶分泌作用存在受体后调节，并且这种调节是VIP和促胰液素对酶分泌作用大小的主要决定因素。反过来，这种调节反映了从细胞内储存库动员的细胞内钙增强细胞内cAMP对酶分泌过程作用的能力。
