胆碱能神经元在闪光刺激增强大鼠初级视皮层可塑性中的作用  

Effects of cholinergic neurons in flashing stimulation enhanced plasticity of primary visual cortex in rats

作　　者：林玲[1] 任京力[2] 

机构地区：[1]漯河医学高等专科学校生理教研室,河南省漯河市462002 [2]漯河医学高等专科学校药理教研室,河南省漯河市462002

出　　处：《眼科新进展》2015年第3期231-234,共4页Recent Advances in Ophthalmology

基　　金：漯河医学高等专科学校2012校级自然科学研究资助项目(编号:2010S07)~~

摘　　要：目的研究胆碱能神经元及递质在大鼠初级视皮层可塑性中的作用。方法36只(36眼)成年SD大鼠随机分为3组:对照组、激动剂组、阻断剂组,每组各12只(12眼)。各组大鼠麻醉、固定后在初级视皮层(V1区)植入记录电极和玻璃微电极、在额叶植入参考电极,术后第7、8、9天于固定时间行紫光闪光刺激1 h,第10天行微量注射M受体激动剂卡巴胆碱和M受体阻断剂东莨菪碱,注射后在相同闪光刺激条件下给予一串高频刺激,记录各组高频刺激前后V1区的视觉诱发电位,分析各组视觉诱发电位的幅值和峰时值的变化。检测不同组别大鼠在强直性闪光刺激后初级视皮层中胆碱乙酰转移酶(ChAT)、胆碱酯酶(AchE)活性,Western blot检测不同组别大鼠初级视皮层ChAT含量。结果对照组和激动剂组在接受强直性闪光刺激后视觉诱发电位幅值较之前有显著性升高(均为P<0.01),且峰时值变短(均为P<0.01),阻断剂组幅值和峰时值在刺激前后差异无统计学意义(均为P>0.05)。在强直性闪光刺激后,与对照组相比,激动剂组幅值升高(P<0.01)、峰时值变短(P<0.01),阻断剂组幅值降低(P<0.01)、峰时值变长(P<0.01)。对不同组别大鼠进行强直性闪光刺激后发现,与对照组相比,激动剂组的ChAT活性明显升高(P<0.05)、AchE活性降低(P<0.05);而阻断剂组的ChAT活性明显降低(P<0.05),AchE活性升高(P<0.05);阻断剂组与激动剂组ChAT、AchE活性差异显著(均为P<0.05)。ChAT蛋白的表达经Western blot分析发现,与对照组比较,激动剂组有显著性升高(P<0.05),阻断剂组有显著性降低(P<0.05),阻断剂与激动剂组差异显著(P<0.05)。结论强直性闪光刺激能使大鼠闪光视觉诱发电位呈现LTP样反应,胆碱能神经元及递质系统参与了闪光刺激致大鼠初级视皮层的可塑性变化。Objective To investigate the effects of cholinergic neurons and neurotransmitters in the plasticity of primary visual cortex in rats. Methods Thirty-six adult Sprague-Dawley rats were divided into three groups： control group,agonist group and blocker group,12 cases（ 12eyes） in each group. All of rats were anesthetized, fixed, implanted recording electrode and glass microelectrode in the primary visual cortex（ V1） and reference electrode in the frontal lobe. Each group of rats were given violet flash stimulation at day 7,day 8,day 9 for 1 hour at fixed time after operation. M-receptor agonist and blocker were injected at day 10, then a string of high-frequency flashing stimulation was applied to the primary visual cortex in the same flash stimulus condition.The flash visual evoked potential（ F-VEP） before and after high-frequency stimulation were recorded in the primary visual cortex（ V1）, and changes of amplitude, as well as peak latency were analyzed in each group. The activity of ChAT and AchE in primary visual cortex were checked after high frequency flash stimulation in different groups,and the expression of ChAT in different groups was detected by Western blot. Results After high-frequency stimulation, the amplitude of the F-VEP was significantly increased（ all P〈0. 01）,and the peak latency were significantly shorter（ all P〈0. 01） both in control group and agonist group. While in the blocker group, there was no significant difference（ all P〈0. 05） in amplitude and peak latency of the F-VEP. Meanwhile,after high-frequency stimulation, compared with the control group, the amplitude of the FVEP was significantly increased and the peak latency was significantly shorter（ all P〈0. 01） in the agonist group,while in the blocker group, it showed amplitude reduction and peak latency lengthen of the F-VEP（ all P〈0. 01）. Compared with the control group after high frequency stimulation,the activity and expression of ChAT were both significantly increased in agonist group（

关 键 词：初级视皮层 视觉诱发电位 M受体 胆碱能神经元 胆碱乙酰转移酶 LTP 

分 类 号：R322.64[医药卫生—人体解剖和组织胚胎学]