Effect of garlicin on sodium channel current in rat ventricular myocytes

AIM: To observe the effect of garlicin on sodium channel(I_Na) in isolated ventricular myocytes of rats. METHODS: The ventricular myocytes of rats were obtained by enzymatic dissociation and treated with different concentrations of garlicin. The change of I_Na was recorded by the technique of whole-cell patch clamp recording.RESULTS: Garlicin decreased the I_Na of isolated ventricular myocytes in a dose- and voltage-dependent manner. The current density was elevated to peak under the condition that the membrane voltage was -40 mV before treated with garlicin. The current density was decreased by 48% from peak after treated with 500 μmol/L garlicin . No significant change of the active curve with the use of garlicin was observed. The median inactive voltages of the inactive curves before and after garlicin treatment were (-88.61±9.60) mV and (-103.03±8.90) mV (P<0.01), respectively, and the slopes were -7.85±0.88 and -7.55±2.75 (P>0.05), respectively, indicating that garlicin made a shift to the negative direction. CONCLUSION: Garlicin treatment induced the current density-voltage curve of I_Na to shift up and significantly decreased the current density. The inactive curve of sodium channel moved to the left, while the current density was not decreased after treated with garlicin. Garlicin blocks sodium channel in its inactive state in a dose- and voltage-dependent manner.