title: Inhibition of cyclic AMP accumulation in dog heart washed particle preparations by aprotinine.
abstract: The effect of aprotinine, a natural non-specific protease inhibitor, on cyclic AMP accumulation in a dog heart washed particle preparation was studied. Aprotinine inhibited GTP-stimulated cyclic AMP accumulation at concentrations equal to or higher than 40 KIU/ml (8 x 10(-7) M). Aprotinine inhibited epinephrine (10(-4) M)-stimulated cyclic AMP accumulation to a greater degree than fluoride (10(-2) M)-stimulated activity. Trypsin stimulated cyclic AMP accumulation at low concentrations (0.5 to 2.5 microgram/ml) and inhibited at higher concentrations. Aprotinine at low concentrations (4 KIU/ml) inhibited the trypsin (1 microgram/ml) stimulation of cyclic AMP accumulation. We conclude that aprotinine may act on the regulator rather than on the catalytic sub-unit of adenylate cyclase and that its mechanism of action is not due only to its antiprotease activity.
mesh_terms: D000818:Animals; D007611:Aprotinin / Q000494:pharmacology*; D000242:Cyclic AMP / Q000378:metabolism*; D003864:Depression, Chemical; D004285:Dogs; D004837:Epinephrine / Q000494:pharmacology; D005459:Fluorides / Q000494:pharmacology; D006160:Guanosine Triphosphate / Q000494:pharmacology; D066298:In Vitro Techniques; D009206:Myocardium / Q000378:metabolism*; D014357:Trypsin / Q000494:pharmacology
chemical_list: D006160:Guanosine Triphosphate; D007611:Aprotinin; D000242:Cyclic AMP; D014357:Trypsin; D005459:Fluorides; D004837:Epinephrine