[Effects of propofol on contractility and electrophysiological properties of canine single cardiomyocytes].
We assessed the effects of propofol on contraction, action potentials and Ca2+ currents (Ica) in single ventricular cells in dog. Low concentrations of propofol 10(-5)M had no effects on contractile responses, but high doses above 10(-4)M of propofol decreased contractions. Propofol 10(-3)M reduced the duration of action potentials (time to 90% repolarization). Ica was decreased by propofol 10(-4)M without accompanying use-dependent manner. The present study indicates that clinical concentrations of propofol do not exert direct negative inotropic effects, but at supratherapeutic concentrations it inhibits cardiac contractility.