摘要
目的:观察常氧葡萄糖剥夺对原代培养大鼠皮层神经元膜上BKCa通道活性的影响。方法:原代培养乳鼠大脑皮层神经元随机分为正常对照组(C)、糖剥夺1 h组(GD1)、糖剥夺2 h组(GD2)、糖剥夺3 h组(GD3)、糖剥夺4 h组(GD4)和糖剥夺5 h组(GD5),采用膜片钳内面向外模式观察无糖能量耗竭模型对神经元BKCa通道的影响。结果:随葡萄糖剥夺后孵育时间的延长(1 h、2 h、3 h、4 h、5 h),细胞形态发生变化,活性下降;虽然葡萄糖剥夺对BKCa单通道电导无明显影响,但是,无糖孵育1 h就明显影响通道活性,使其平均开放概率(NPo)和通道平均开放时间(To)显著增加,伴平均关闭时间(Tc)的缩短。在葡萄糖剥夺2 h、3 h到4 h的过程中,其NPo渐加大,To渐延长,Tc则渐缩短。在葡萄糖剥夺5 h时,较4 h的NPo降低,To稍减少,Tc稍延长。结论:葡萄糖缺乏1 h就可使BKCa通道过度激活,使神经元超极化,葡萄糖缺乏5 h可能损伤通道功能。
Objective： To investigate the effects of glucose deprivation （GD） on the activation of large-conductance Ca2＋ -activated K＋ channels （BKCa） in primary cultured rat cortex neurons. Methods： The primary cultured rat cortex neurons were randomly assigned to control group, GD for I h, GD for 2h, GD for 3h, GD for 4h, GD for 5h group. Inside-out patch clamp was used to record the single channel conductance. Results： cells morphology were changed with the prolonged glucose deprivation（lh,2h,3h,4h,5h） and the activity of cells decreased. Although glucose deprivation did not affect the single channel conductance, the open probability （NPo） was significantly in- creased to over 2 -fold after glucose deprivation for lh. Moreover, glucose deprivation significantly increased the average open time （To） and decreased the average closed time of BKCa channels. The similar trend was seen in glucose deprivation for 2h,3h and 4h. The NPo and To were slightly decreased and the Tc was slightly increased after glucose deprivation for 5h. Conclusion： These data suggest that glucose deprivation for l h can excessively ac- tivate the BKCa channels in the primary cultured rat cortex neurons, which make the neurons hyperpolariza- tion. But glucose deprivation for 5h may injury these channels.
出处
《北京体育大学学报》
CSSCI
北大核心
2013年第12期68-72,共5页
Journal of Beijing Sport University
基金
中央高校基本科研业务费专项资金资助课题(2012QN009)
教育部新世纪优秀人才支持计划资助项目(2010年)
