Adenylyl Cyclase 3 Mediates Prostaglandin E2-induced Growth Inhibition in Arterial Smooth Muscle Cells

Scott T. Wong, Lauren P. Baker, Kien Trinh, Michal Hetman, Lucy A. Suzuki, Daniel R. Storm, Karin E. Bornfeldt
2001 Journal of Biological Chemistry  
Arterial smooth muscle cell (SMC) proliferation contributes to a number of vascular pathologies. Prostaglandin E 2 (PGE 2 ), produced by the endothelium and by SMCs themselves, acts as a potent SMC growth inhibitor. The growth-inhibitory effects of PGE 2 are mediated through activation of G-protein-coupled membrane receptors, activation of adenylyl cyclases (ACs), formation of cAMP, and subsequent inhibition of mitogenic signal transduction pathways in SMCs. Of the 10 different mammalian AC
more » ... orms known today, seven isoforms (AC2-7 and AC9) are expressed in SMCs from various species. We show that, despite the presence of several different AC isoforms, the principal AC isoform activated by PGE 2 in human arterial SMCs is a calmodulin kinase II-inhibited AC with characteristics similar to those of AC3. AC3 is expressed in isolated human arterial SMCs and in intact aorta. We further show that arterial SMCs isolated from AC3-deficient mice are resistant to PGE 2 -induced growth inhibition. In summary, AC3 is the principal AC isoform activated by PGE 2 in arterial SMCs, and AC3 mediates the growth-inhibitory effects of PGE 2 . Because AC3 activity is inhibited by intracellular calcium through calmodulin kinase II, AC3 may serve as an important integrator of growth-inhibitory signals that stimulate cAMP formation and growth factors that increase intracellular calcium. Proliferation of arterial smooth muscle cells (SMCs) 1 contributes to several cardiovascular diseases such as atherosclerosis (1, 2). The intracellular second messenger cAMP markedly inhibits proliferation of SMCs and antagonizes growth factorstimulated activation of the extracellular signal-regulated kinase pathway and the S6 kinase 1 (S6K1) pathway and acti-
doi:10.1074/jbc.m103923200 pmid:11432866 fatcat:aewg3pcs65bi7lqtcwmplnjnrq