Bode D C, Brunton L L
Department of Pharmacology, University of California, San Diego, La Jolla 92093.
Mol Cell Biochem. 1988 Jul-Aug;82(1-2):13-8. doi: 10.1007/BF00242510.
The actions of cyclic AMP are subject to several levels of post-receptor modulation in cardiac tissue. Isoproterenol and prostaglandin E1 both stimulate cAMP accumulation, but only isoproterenol causes activation of particulate cAMP-dependent protein kinase, leading to activation of phosphorylase kinase and glycogen phosphorylase, and inhibition of glycogen synthase. Through the use of isolated, adult ventricular myocytes, we have determined that the hormone-specific activation of glycogen phosphorylase is due to subcellular compartmentation of cAMP. There is some evidence that cyclic nucleotide phosphodiesterases, whose activity is stimulated by alpha 1-adrenergic agonists in isolated myocytes, may have a role in compartmentation. Phosphoinositide hydrolysis is stimulated by alpha 1 and muscarinic agonists, presumably leading to activation of protein kinase C, which in turn has multiple effects on hormone-sensitive adenylate cyclase.
环磷酸腺苷（cAMP）的作用在心脏组织中受到受体后多个水平的调节。异丙肾上腺素和前列腺素E1均刺激cAMP积累，但只有异丙肾上腺素能激活颗粒型cAMP依赖性蛋白激酶，导致磷酸化酶激酶和糖原磷酸化酶激活，并抑制糖原合酶。通过使用分离的成年心室肌细胞，我们已确定糖原磷酸化酶的激素特异性激活是由于cAMP的亚细胞分隔。有证据表明，环核苷酸磷酸二酯酶的活性在分离的肌细胞中受到α1肾上腺素能激动剂的刺激，可能在分隔中起作用。α1和毒蕈碱激动剂刺激磷酸肌醇水解，推测导致蛋白激酶C激活，而蛋白激酶C继而对激素敏感的腺苷酸环化酶有多种作用。
