Effects of WIN 55, 212-2 onI_K current in cultured trigeminal ganglion neurons of rat

Abstract

To investigate the effects of WIN 55, 212-2 onI_K in cultured rat trigeminal ganglion (TG) neurons, whole-cell patch clamp techniques were used to record theI_K before and after WIN 55,212-2 perfusion at different concentrations. 30 μmol/L WIN 55,212-2 markedly (35.7%±7.3%P<0.01,n=8) inhibitedI_K currents, and the currents were partially recovered after washing. 30 μmol/L WIN 55, 212-2 also induced a significant depolarizing shift in conductance-voltage parameters (control: V_0.5=10.43±4.25 mV, k=16.27±3.86; WIN 55,212-2: V_0.5=24.71±3.91 mV, k=16.69±2.75;n=8,P<0.01 for V_0.5). 0.01 μmol/L WIN 55,212-2 slightly (27.0%±7.9%,P<0.05,n=7) increasedI_K currents, but had no significant change in conductance-voltage parameters (control: V_0.5=10.74±5.27 mV, k=17. 33±2.96; WIN 55, 212-2: V_0.5=11.06±2.05 mV, k=19.69±6.60;n=7,P>0.05 for V_0.5 and k). These results suggested that WIN 55, 212-2 has dual action, which might be through different receptors.

Keywords

WIN 55, 212-2 / trigeminal ganglion neuron / I_K current / rat

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