Effects Of Alpha-Asarone On Transient Outward Potassium Current In Sombati’s Cell Of Epilepsy And Hippocampal Neurons

OBJECTIVE:To observe changes in transient outward potassium current (IA) in Sombati’s cell of epilepsy and hippocampal neurons cultured in vior, after intervention with various concentrations of a-asarone, explore the effects of a-asarone on IA preliminarily in Sombati’s model of epilepsy and its neuroprotection.Methods:Dissociated hippocampal neurons from neonatal SD rats were cultured in vitro in the serum-free neurobasal medium adding B-27supplement.At8days part of neurons were randomly divided to induce Sombati’s model.In our studies,we divided neurons into normal control group,model control groupd, and the respective3concentrations of alpha-asarone-treated group.The whole-cell patch-clamp technique was used to record IA of hippocampal neurons in normal control group, model control group, and the respective alpha-asarone-treated groups after24h intervention with15μg/ml,30μg/ml and60μg/ml α-asarone. Results:(1) Compared with normal control group, the IA peak increased significantly in model control group, with difference of statistical significance;(2) Compared with normal control group, the IA peak increased significantly in the3concentrations of alpha-asarone-treated normal groups, the IA peak in the3concentrations of drug treatment groups increased with higher a-asarone concentrations. the difference in IA peak among the3concentrations of drug treatment groups had statistical significance.(3)The difference in IA peak among the3concentrations of alpha-asarone-treated groups had statistical significance. Compared with model control group, the IA peak in the3concentrations of alpha-asarone-treated model groups increased with higher a-asarone concentrations.Conclusion:(1) IA increases significantly in Sombati’s epileptic cells; possibly representing a compensatory self-protecting mechanism to maintain intracellular homeostasis after epileptic cells epileptiform discharge.(2) We presumably the protection of a-asarone on hippocampal neuron under physiological status may be related to the cellular protection on improving cerebral blood flow and learning memory by opening A-type potassium channel so as to increase IA.(3) Alphan-asarone intervention further increases IA in Sombati’s epileptic cells and presumably exerts its anti-epileptic and neuroprotective effects roles through type-A potassium channels in these cells.