Perkins J P, Su Y F, Harden T K
Drug Alcohol Depend. 1979 May-Jul;4(3-4):279-94. doi: 10.1016/0376-8716(79)90011-5.
Exposure of the intact astrocytoma cell to isoproterenol not only causes the activation of adenylate cyclase and the accumulation of cyclic AMP but sets in motion a complicated series of events designed to down-regulate the system if exposure to the agonist is extended in time. We have identified at least three of these processes: (1) a rapid uncoupling of the beta-receptor--adenylate cyclase system with subsequent loss of beta-receptors; (2) a slower, nonspecific desensitization of adenylate cyclase to the effects of all classes of receptor agonists by a process that may be mediated by cyclic AMP; and (3) a slow induction of phosphodiesterase activity that is probably mediated by cyclic AMP.
完整的星形细胞瘤细胞暴露于异丙肾上腺素不仅会导致腺苷酸环化酶的激活和环磷酸腺苷(cAMP)的积累,而且如果延长对激动剂的暴露时间,还会引发一系列复杂的事件,旨在下调该系统。我们已经确定了这些过程中的至少三个:(1)β受体 - 腺苷酸环化酶系统的快速解偶联以及随后β受体的丧失;(2)腺苷酸环化酶对所有类型受体激动剂作用的较慢、非特异性脱敏,这一过程可能由环磷酸腺苷介导;(3)磷酸二酯酶活性的缓慢诱导,这可能由环磷酸腺苷介导。