Summers S T, Cronin M J
Department of Physiology, University of Virginia School of Medicine, Charlottesville 22908.
Arch Biochem Biophys. 1988 Apr;262(1):12-8. doi: 10.1016/0003-9861(88)90162-2.
Phorbol esters alter cyclic AMP levels in a number of tissues, including the anterior pituitary. We report that membrane preparations from GH3 cells exposed to phorbol esters exhibit decreased vasoactive intestinal peptide (VIP)-stimulated and enhanced forskolin-stimulated adenylate cyclase activity. The responsiveness of adenylate cyclase activity to NaF, guanylyl-imidodiphosphate, and Mn2+ was also reduced by phorbol ester treatment. The ability of somatostatin to inhibit forskolin-stimulated adenylate cyclase activity was reduced while phorbol ester exposure had no apparent effect on somatostatin inhibition of VIP-stimulated adenylate cyclase activity. We suggest that protein kinase C alters at least two distinct components of the adenylate cyclase system. One modification disrupts hormone receptor-Gs interaction (lowering VIP efficacy) and the second perturbation augments the activity of the adenylate cyclase catalytic subunit.
佛波酯可改变包括垂体前叶在内的多种组织中的环磷酸腺苷水平。我们报告称，暴露于佛波酯的GH3细胞膜制剂显示，血管活性肠肽（VIP）刺激的腺苷酸环化酶活性降低，而福斯高林刺激的腺苷酸环化酶活性增强。佛波酯处理也降低了腺苷酸环化酶活性对氟化钠、鸟苷酰亚胺二磷酸和锰离子的反应性。生长抑素抑制福斯高林刺激的腺苷酸环化酶活性的能力降低，而暴露于佛波酯对生长抑素抑制VIP刺激的腺苷酸环化酶活性没有明显影响。我们认为蛋白激酶C改变了腺苷酸环化酶系统的至少两个不同组分。一种修饰破坏了激素受体与Gs的相互作用（降低VIP效力），第二种干扰增强了腺苷酸环化酶催化亚基的活性。
