无镁诱导培养大鼠海马神经元癫痫放电模型电压门控性钠通道Na_v1.1和钙调蛋白的异常表达  

The abnormal expression and distribution of voltage-gated sodium channel Na_v1.1 and calmodulin in cultured rat hippocampal Mg^(2+)-free neuronepileptiform discharge model

作　　者：郭凤[1] 陈达[2] 马丽华[1] 孙雪菲[1] 徐晓雪[3] 吕昕瞳[1] 胡慧媛[1] 赵金生[1] 封瑞[1] 蔡际群[1] 

机构地区：[1]中国医科大学药学院药物毒理教研室,辽宁沈阳110001 [2]中国医科大学附属四院急诊内科,辽宁沈阳110001 [3]中国医科大学附属一院神经内科,辽宁沈阳110001

出　　处：《解剖科学进展》2013年第4期303-306,共4页Progress of Anatomical Sciences

基　　金：国家自然科学基金资助项目(No.81001429;81100108;30270535)

摘　　要：目的利用无镁细胞外液诱导原代培养大鼠海马神经元癫痫放电模型来检测电压门控性钠通道Nav1.1和钙调蛋白的表达与定位。方法采用新生24h内Wistar大鼠,取海马进行神经元原代培养。体外培养至10d,无镁细胞外液处理(实验组)或正常细胞外液(对照组)处理神经元3h后,一部分细胞应用全细胞膜片钳技术记录神经元的放电情况并应用免疫印迹法检测电压门控性钠通道Nav1.1和钙调蛋白的蛋白表达;另一部分细胞用正常培养液继续培养12h后分别通过免疫印迹法和免疫荧光双标法检测Nav1.1和钙调蛋白的蛋白表达与共定位。结果无镁细胞外液处理3h后的神经元存在自发的"癫痫样"放电,而与正常细胞外液处理组相比,Nav1.1和钙调蛋白表达不变;无镁处理3h正常培养液再继续培养12h后,与正常细胞外液处理组相比,神经元Nav1.1表达上调,而钙调蛋白表达不变。另外,与正常细胞外液处理组相比,Nav1.1和钙调蛋白共定位的阳性细胞数增加。结论 Nav1.1和钙调蛋白的表达与定位变化可能与无镁诱导体外培养大鼠海马神经元自发异常放电的基础病理机制相关。Objective To detect the expression and distribution change of voltage-gated sodium channel Nav1.1 and calmodulin（CaM） in cultured rat hippocampal Mg^2＋-free neuron. Methods The postnatal hippocampal tissue was taken out from 1-day-old Wistar rats and used for primary culture. From the IOn day, neurons were treated with magnesium-free extracellular fluid or normal extracellular fluid for 3h, and the discharge activity was recorded by patch clamp. For one part of neurons, the protein expressions of Nav1.1 and CaM Were detected by Westem blot after magnesium-free extracellular fluid treatment for 3h. The other part of neurons were treated with normal cultured fluid 12h after magnesium-free extracellular fluid treatment for 3h, then the protein expression and distribution of Nav1.1 and CaM were detected by Western blot and immunofluorescence. Results Neurons showed spontaneous ＂epileptiform discharge＂ after magnesium-free extracellular fluid treatment for 3h, but with no difference for the two proteins expression levels between magnesium-free group after magnesium-free extracellular fluid treatment for 3h and normal control group. However, the protein expression level of Nav1.1 was up-regulated and CaM was unchanged, the number of colocalization cells for Nav1.1 and CaM was increased in magnesium-free group compared with normal control group after normal cultured fluid treatment for 12h. Conclusion The abnormal expression and distribution of voltage-gated calcium channel Nav1.1 and CaM might be related to the underlying mechanism of spontaneous ＂epileptiform discharge＂ in Mg^2＋-free neuron model.

关 键 词：海马 膜片钳 电压门控性钠通道 钙调蛋白 大鼠 

分 类 号：R338.26[医药卫生—人体生理学]