Inhibition of rabbit cardiac adenylate cyclase by theophylline.
Theophylline inhibits basal adenylate cyclase activity as well as cyclase stimulated by sodium chloride, sodium fluoride, GTP or 5'-guanylimidodiphosphate. This inhibition, is dose-dependent and shows non-competitive inhibition, with respect to MgATP. The presence of adenosine deaminase does not alter the effect of theophylline. The inhibition produced by theophylline is not additive with that due to 2'-deoxyadenosine 3'-monophosphate (a P-site agonist). It is suggested that theophylline may act at the P-site to reduce adenylate cyclase activity.
Hopwood
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Harding
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Harris
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D000243:Adenosine Deaminase / Q000378:metabolism; D000067956:Adenylyl Cyclase Inhibitors; D000818:Animals; D006160:Guanosine Triphosphate / Q000494:pharmacology; D006165:Guanylyl Imidodiphosphate / Q000494:pharmacology; D066298:In Vitro Techniques; D007700:Kinetics; D008297:Male; D009206:Myocardium / Q000201:enzymology*; D011817:Rabbits; D012969:Sodium Fluoride / Q000494:pharmacology; D013806:Theophylline / Q000494:pharmacology*
D000067956:Adenylyl Cyclase Inhibitors; D006165:Guanylyl Imidodiphosphate; D006160:Guanosine Triphosphate; D012969:Sodium Fluoride; D013806:Theophylline; D000243:Adenosine Deaminase