Endothelin subtype B receptors are coupled to adenylate cyclase via inhibitory G protein in cultured bovine endothelial cells.
We studied whether endothelin (ET) isopeptides have any effects on adenylate cyclase activity in cultured bovine endothelial cells (ECs). Both ET-1 and ET-3 dose-dependently inhibited cAMP formation stimulated by forskolin and isoproterenol, although the inhibitory effect of ET-1 was less potent than that of ET-3. In contrast, ET-1 and ET-3 almost equipotently inhibited forskolin-stimulated cAMP formation in bovine EC pretreated with phosphoramidon, a putative ET-1 converting-enzyme inhibitor. These data suggest that endothelial ETB receptors are functionally coupled to adenylate cyclase, possibly via Gi protein.
Eguchi
S
S
Second Department of Internal Medicine, Tokyo Medical and Dental University, Japan.
Hirata
Y
Y
Marumo
F
F
D000262:Adenylyl Cyclases / Q000378:metabolism*; D000818:Animals; D002417:Cattle; D002478:Cells, Cultured; D005576:Colforsin / Q000494:pharmacology; D000242:Cyclic AMP / Q000378:metabolism; D065128:Endothelin Receptor Antagonists; D004730:Endothelium, Vascular / Q000187:drug effects / Q000201:enzymology* / Q000378:metabolism; D019204:GTP-Binding Proteins / Q000378:metabolism*; D006020:Glycopeptides / Q000494:pharmacology; D007545:Isoproterenol / Q000494:pharmacology; D009569:Nitric Oxide / Q000494:pharmacology; D017466:Receptors, Endothelin / Q000187:drug effects / Q000378:metabolism*
D065128:Endothelin Receptor Antagonists; D006020:Glycopeptides; D017466:Receptors, Endothelin; D005576:Colforsin; D009569:Nitric Oxide; D000242:Cyclic AMP; D019204:GTP-Binding Proteins; D000262:Adenylyl Cyclases; D007545:Isoproterenol; C008890:phosphoramidon