EffectsofWIN55,212-2onIKCurrentinCulturedTrigeminalGanglionNeuronsofRat

Summary: To investigate the effects of WIN 55,212-2 on I K in cultured rat trigeminal ganglion (TG) neurons, whole-cell patch clamp techniques were used to record the I 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) inhibited I 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) increased I 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.