Distinct functions of down-regulation-sensitive and -resistant types of protein kinase C in rabbit aortic smooth muscle cells.
In quiescent cultures of rabbit aortic smooth muscle cells, 12-O-tetradecanoylphorbol-13-acetate (TPA) induced DNA synthesis to some extent in the presence of rabbit plasma-derived serum but inhibited the rabbit whole blood serum (WBS)-induced DNA synthesis and increase in cytoplasmic free Ca2+ concentration Ca2+]i). Prolonged treatment of the cells with phorbol-12,13-dibutyrate (PDBu) caused the partial down-regulation of protein kinase C to a level of 25-35% of that in control cells. In these PDBu-pretreated cells, TPA neither induced DNA synthesis nor inhibited the WBS-induced DNA synthesis, but still inhibited the WBS-induced increase in [Ca2+]i. These results suggest that there are down-regulation-sensitive and -resistant types of protein kinase C in rabbit aortic smooth muscle cells; that the down-regulation-sensitive type has the proliferative and antiproliferative actions whereas the down-regulation-resistant type lacks them; and that the down-regulation-resistant type has the activity to inhibit the WBS-induced increase in [Ca2+]i.
Kariya
K
K
Takai
Y
Y
D000818:Animals; D001013:Aorta, Thoracic / Q000201:enzymology; D002118:Calcium / Q000378:metabolism; D003593:Cytoplasm / Q000378:metabolism; D004247:DNA / Q000096:biosynthesis; D004351:Drug Resistance; D008297:Male; D009131:Muscle, Smooth, Vascular / Q000201:enzymology*; D015240:Phorbol 12,13-Dibutyrate; D010703:Phorbol Esters / Q000494:pharmacology; D011493:Protein Kinase C / Q000037:antagonists & inhibitors / Q000378:metabolism*; D011817:Rabbits; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
D010703:Phorbol Esters; D015240:Phorbol 12,13-Dibutyrate; D004247:DNA; D011493:Protein Kinase C; D013755:Tetradecanoylphorbol Acetate; D002118:Calcium