EFFECT OF PALMITOYLCARNITINE ON THE PASSIVE ELECTRICAL-PROPERTIES OF ISOLATED GUINEA-PIG VENTRICULAR MYOCYTES

The effects of palmitoylcarnitine (PC) on the passive electrical properties of isolated guinea pig ventricular myocytes were studied using conventional microelectrode techniques. The amphiphile depolarized the cell membrane, and at low concentration (10(-6) M), increased the input resistance (R(in)) from 12.4 to 17.9 M-OMEGA and the time constant (tau-m) from 1.38 to 2.20 ms. A higher concentration of PC (10(-5) M) decreased R(in) to 8.5 M-OMEGA and tau-m to 1.14 ms. No significant change was observed in the membrane capacitance and in the capacitative membrane area. The results suggest that PC incorporates into the cell membrane and in low concentration, it increases the membrane resistance, while its high concentration increases the membrane permeability probably by causing serious damages in the membrane structure.