Effects of Buyang Huanwu Decoction on L-type Calcium Channels of Cortical Neurons in Rats with Global Cerebral Ischemia and Reperfusion at Different Time Points / 广州中医药大学学报

ABSTRACT

【Objective】 The effect of pretreatment with Buyang Huanwu Decoction(BHD) on L-type calcium channels of cortical neurons in rats with global cerebral ischemia was observed,thus to explore the molecular therapeutic mechanism of BHD for cerebral ischemia as well as the pathogenic mechanism of Ca2+ message in ischemic injury of neurons.【Methods】SD rats were randomized into pseudo-operation group,model groups and BHD groups.And the model groups and BHD groups were divided into six groups according to the time points after reperfusion(2nd,12th,24th,48th and 72nd hour after reperfusion respectively).BHD groups received 0.64g/kg BHD by gastric infusion,bid,for 5 continuous days.Except the rats in pseudo-operation groups,the rats in other groups were induced global cerebral ischemia by modified Pulsinelli's four-vessel occlusion.Cerebral cortical neurons in rats were isolated promptly in 2nd,12th,24th,48th and 72nd hour after reperfusion.The recorded single-channel current was amplified by the EPC-9 patch-clamping amplifier,and then input into the computer by Pulse+Pulsefit.The analytical software TAC was used to detect the opening time and opening probability of the L-type Ca2+ channels in rats at different time points after reperfusion.【Results】In the model groups,the opening time of the L-type Ca2+ channels was prolonged after reperfusion as compared with that in the pseudo-operation group,and the opening probability of the L-type Ca2+ channels arrived at the peaks in 2nd and 24th hour after reperfusion.In BHD groups,the opening time in 72nd hour after reperfusion was decreased(P