Chronic diabetes decreases the ouabain inotropic response in rat left atria and papillary muscles.
The inotropic response to ouabain in rat left atria were markedly depressed in animals made diabetic for 6 months. Similarly, ouabain inotropy was also decreased in papillary muscles obtained from 70-day diabetic rats. The effect of isoproterenol was not reduced in the above papillary muscle experiments and was not tested in the atria experiments. Ouabain produced a monophasic dose-response curve in atria but a biphasic curve in papillary muscles. Timolol had no effect on the ouabain response. Left atria and papillary muscles from animals made diabetic for 7 days responded in a normal fashion to both ouabain and isoproterenol.
D000818:Animals; D003921:Diabetes Mellitus, Experimental / Q000503:physiopathology*; D005260:Female; D066298:In Vitro Techniques; D007545:Isoproterenol / Q000494:pharmacology; D009200:Myocardial Contraction / Q000187:drug effects*; D010042:Ouabain / Q000494:pharmacology*; D010210:Papillary Muscles / Q000502:physiology; D051381:Rats; D011919:Rats, Inbred Strains; D011955:Receptors, Drug / Q000032:analysis; D000254:Sodium-Potassium-Exchanging ATPase / Q000032:analysis
D011955:Receptors, Drug; C028996:cardiac glycoside receptors; D010042:Ouabain; D000254:Sodium-Potassium-Exchanging ATPase; D007545:Isoproterenol