【摘要】 目的：探讨一次和重复力竭运动对纹状体背外侧神经元电活动的影响及可能的调节机制。方法：8周龄健康雄性Wistar大鼠，随机分为安静对照组（CG）、一次力竭运动组（EG）、7天重复力竭运动组（REG），每组24只，其中6只做电生理实验。采用在体多通道电生理技术记录大鼠在清醒安静状态下，一次力竭运动和7天重复力竭运动后大鼠纹状体背外侧的神经元放电活动；采用免疫荧光双染技术观察各组大鼠纹状体背外侧小青蛋白（Parvalbumin,PV）及NMDAR2B阳性神经元的表达。结果：（1）与安静状态相比，一次力竭运动后大鼠纹状体背外侧中等多棘神经元（medium spiny neuron,MSN）放电频率未发生显著改变（P>0.05），而重复力竭运动后MSN放电频率明显升高（P<0.01）;(2)一次和重复力竭运动后大鼠纹状体背外侧局部场电位γ频段的功率谱密度均较安静状态有明显增加（P<0.01），重复力竭运动后增加更为明显，且与一次力竭运动后相比有明显差异（P<0.05）;(3)一次和重复力竭运动组大鼠纹状体背外侧PV阳性神经元表达较安静对照组有显著增加（P<0.01）;NMDAR2B在各组均有明显表达，重复力竭运动组NMDAR2B与PV阳性神经元共表达神经元个数较安静对照组明显增加（P<0.01）。结论：重复力竭运动与一次运动产生疲劳在中枢调节中有所不同。纹状体背外侧在一次力竭运动引起的疲劳中调节作用不明显，在重复力竭运动引起的疲劳中调节作用增强，NMDAR2B参与介导了纹状体背外侧PV神经元对MSN的兴奋性调控。更多还原

【Abstract】 ObjectiveTo explore the effect of one-time and repeated exhaustive exercises on the electrical activity of neurons in the dorsal lateral striatum and its possible regulation mechanism.MethodsEight-week male healthy Wistar rats were randomly divided into a control group(CG),an exhaustive group(EG) and a repeated exhaustive group(REG),each of 24 rats,including 6 rats which were used for the electrophysiological experiment. CG did no sport,while EG and REG did one-time and seven-day repeated exhaustive exercises respectively. Then their neuronal activities of the dorsolateral striatum were recorded using the multi-channel in vivo recording method. Meanwhile,the immunofluorescence method was used to determine the parvalbumin(PV) and NMDAR2B positive neurons expression in the dorsolateral striatum.ResultsCompared with CG,a significant increase was observed in the firing frequency of the medium spiny neuron(MSN) in REG(P<0.01),without any differences in that of EG(P>0.05). The average power spectral density of the local field potential gamma band increased significantly in EG and REG groups,with more significant increase in REG than in EG,compared with CG. A significant increase was observed in the number of PV positive neurons in the exercise groups compared with CG,while there was a significant increase in the average number of NMDAR2B positive neurons of all groups,with that of REG significantly greater than CG(P<0.01).Conclusions Fatigue induced by one-time and repeated exhaustive exercises is regulated differently in the central nervous system,as the dorsolateral striatum plays an important role in the regulation of repeated-training induced fatigue,but not in the one-time exhaustive exercise. Moreover,NMDAR2B is involved in mediating the excitatory regulation of MSN by neurons PV of the dorsolateral striatum.更多还原