The effects of anthopleurin-A on cardiac dynamics in conscious dogs.
The effects of anthopleurin-A (AP-A), a selective cardiotonic drug, on cardiac dynamics in intact, awake animals were examined. Dogs were instrumented in order to record left ventricular pressure, the derivative of left ventricular pressure (dP/dt), arterial pressure left ventricular end-systolic and end-diastolic diameters, cardiac output, left atrial pressure and heart rate. Left ventricular pressure, dP/dt, stroke volume and cardiac output were significantly increased (16, 46, 37 and 23%, respectively) by AP-A. AP-A significantly diminished heart rate 9 beats/min and left ventricular end-systolic diameter 1.9 mm. Mean arterial pressure, mean left atrial pressure and left ventricular end-diastolic diameter were unaltered by AP-A. Autonomic blockade with atropine and propranolol did not alter these responses on the myocardium qualitatively. Thus, it appears that AP-A has a direct positive inotropic effect on the myocardium in conscious animals with little or no effect on the peripheral circulation.
D000818:Animals; D001285:Atropine / Q000494:pharmacology; D004285:Dogs; D004305:Dose-Response Relationship, Drug; D006321:Heart / Q000187:drug effects*; D006339:Heart Rate / Q000187:drug effects; D006439:Hemodynamics / Q000187:drug effects; D036341:Intercellular Signaling Peptides and Proteins; D009200:Myocardial Contraction / Q000187:drug effects*; D010455:Peptides / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D011433:Propranolol / Q000494:pharmacology; D012615:Sea Anemones; D013268:Stimulation, Chemical; D014655:Vascular Resistance / Q000187:drug effects
D036341:Intercellular Signaling Peptides and Proteins; D010455:Peptides; C012746:anthopleurin-A; D001285:Atropine; D011433:Propranolol