The effects of PGE2 on vasopressin--and guanine nucleotide-mediated adenylate cyclase activity in toad bladder membrane.
PGE2 inhibited 10 m U/ml vasopressin-induced osmotic water flow of the toad bladder at 2 X 10(-8) M. PGE2 suppressed vasopressin-mediated cyclic AMP accumulation in epithelial cells and also vasopressin-mediated adenylate cyclase activity in a crude homogenate of the cells. However, PGE2 had no effect on cyclic AMP dependent and independent protein phosphorylation. These findings indicate that PGE2 inhibits vasopressin-induced water flow mainly through suppression of adenylate cyclase activity, and that the role of PGE2 at that point in the reaction leading to increased water permeability following cyclic AMP production may be slight. Under conditions in which the hormone and substrate are depleted, PGE2 and guanine nucleotides, such as GTP and Gpp(NH)p, additively bring about an increase in adenylate cyclase activity.
Shimada
H
H
Mishina
T
T
Marumo
F
F
D000262:Adenylyl Cyclases / Q000378:metabolism*; D000818:Animals; D002025:Bufonidae; D002462:Cell Membrane / Q000201:enzymology; D000242:Cyclic AMP / Q000096:biosynthesis; D015232:Dinoprostone; D006150:Guanine Nucleotides / Q000494:pharmacology*; D006160:Guanosine Triphosphate / Q000494:pharmacology; D006165:Guanylyl Imidodiphosphate / Q000494:pharmacology; D009995:Osmosis / Q000187:drug effects; D010750:Phosphoproteins / Q000378:metabolism; D010766:Phosphorylation; D011458:Prostaglandins E / Q000494:pharmacology*; D001743:Urinary Bladder / Q000187:drug effects / Q000201:enzymology*; D014667:Vasopressins / Q000494:pharmacology
D006150:Guanine Nucleotides; D010750:Phosphoproteins; D011458:Prostaglandins E; D014667:Vasopressins; D006165:Guanylyl Imidodiphosphate; D006160:Guanosine Triphosphate; D000242:Cyclic AMP; D000262:Adenylyl Cyclases; D015232:Dinoprostone