Cardiac effects of clonidine on isolated dog atria.
The effect of clonidine on pacemaker activity and contractility was studied in the isolated dog atrium which was perfused with arterial blood of the support dog. Clonidine caused dose-dependent negative chronotropic and inotropic effects, and a large dose of clonidine slightly suppressed the positive chronotropic and inotropic responses to norepinephrine and sympathetic cardiac nerve stimulation (5 and 30 Hz) but not consistently.
D000818:Animals; D003000:Clonidine / Q000494:pharmacology*; D004285:Dogs; D004305:Dose-Response Relationship, Drug; D006321:Heart / Q000187:drug effects* / Q000294:innervation; D006339:Heart Rate / Q000187:drug effects; D066298:In Vitro Techniques; D009200:Myocardial Contraction / Q000187:drug effects; D013564:Sympathetic Nervous System / Q000502:physiology
D003000:Clonidine