Effects of bupivacaine on membrane currents of guinea-pig ventricular myocytes

Abstract

The effects of bupivacaine on the membrane currents of single guinea-pig ventricular myocytes were investigated using the whole-cell patch-clamp technique. Bupivacaine decreased the inward calcium current in a concentration-dependent way at concentrations of 10 μM and higher. Bupicavaine also decreased the delayed outward current without modifying the inward-rectifying potassium current. From these results it can be concluded that bupivacaine, at concentrations lower than 10 μM, does not exert its negative inotropic effect by decreasing the calcium current . This mechanism may play a role at higher concentrations of the drug.