Hemodynamic effects of pyruvate infusion in dogs.
OBJECTIVE
Although pyruvate supplementation enhances endurance in humans and increases cardiac output in dogs, its effects on cardiac and peripheral vascular function are not known. Thus, we assessed the cardiovascular effects of pyruvate infusion.


METHODS
Aortic, left ventricular (LV), and pulmonary (Ppa) pressures and LV stroke volume (Svlv; derived from aortic flow probe) were measured after thoracotomy in eight anesthetized dogs. LV area or volume changes were measured using either an epicardial echocardiography (n = 6) or a conductance catheter (n = 2). LV end-systolic elastance (Eeslv) and preload recruitable stroke force (PRSFlv) relations, as estimates of contractility, were generated by transient inferior vena cava occlusion. Simultaneous stroke volume to arterial pressure relations during the occlusions were used to measure arterial elastance (Ea), and steady-state systemic and pulmonary vascular resistances were used as measures of arterial tone. Graded doses of pyruvate (8, 16, and 32 mg/kg/min), dobutamine (positive control) and propranolol (negative control) and placebo (volume control) were sequentially given.


RESULTS
Dobutamine increased Eeslv, PRSFlv, whereas propranolol had the opposite effect on Eeslv and PRSFlv. Pyruvate at 32 mg/kg/min increased heart rate, Ppa, and SVlv and decreased LV end-diastolic area, and systemic vascular resistance without changing arterial pressure, Eeslv, PRSFlv, or Ea.


CONCLUSIONS
We conclude that pyruvate infusion in normal dogs induces venodilation but does not alter either cardiac contractility or arterial tone.
Romand
J A
JA
Department of Anesthesiology and Critical Care Medicine, University of Pittsburgh Medical Center, PA, USA.
Gorcsan
J
J
Stanko
R T
RT
D000818:Animals; D002316:Cardiotonic Agents / Q000494:pharmacology; D004195:Disease Models, Animal; D004280:Dobutamine / Q000494:pharmacology; D004285:Dogs; D004305:Dose-Response Relationship, Drug; D004353:Drug Evaluation, Preclinical; D006439:Hemodynamics / Q000187:drug effects*; D007262:Infusions, Intravenous; D008297:Male; D011433:Propranolol / Q000494:pharmacology; D019289:Pyruvic Acid / Q000494:pharmacology*; D014665:Vasodilator Agents / Q000494:pharmacology
D002316:Cardiotonic Agents; D014665:Vasodilator Agents; D004280:Dobutamine; D019289:Pyruvic Acid; D011433:Propranolol