探究力竭运动对大鼠“丘脑腹外侧核(VL)-皮层辅助运动区(SMA)”通路电活动影响,揭示基底神经节信息输出核团在运动疲劳中枢调控中的作用。方法:Wistar大鼠随机分为对照组、力竭组和干预组,Bedford改良跑台递增负荷运动方案建立一次性力竭运动模型。采用金属电极采集SMA局部场电,对其波形、功率谱密度、平均总功率及各波段所占百分比进行分析;干预组在VL注射γ-氨基丁酸A型受体拮抗剂荷包牡丹碱(BIC)后记录SMA局部场电变化。结果:1)力竭运动后,大鼠SMA局部场电放电频率降低,能量分布低于对照组,辅助运动区兴奋性降低;2)BIC注射干预VL后,SMA局部场电活动信号振幅变小、频率增高、活性增强,总功率显著增高;δ波比例显著降低,α波与β波比例显著升高。结论:力竭运动导致大鼠SMA神经元电活动减弱,“VL-SMA”通路出现抑制现象,而γ-氨基丁酸A型受体拮抗剂荷包牡丹碱干预可以减弱力竭运动引起的基底神经节信息输出通路抑制效应。
Objective:To investigate the "lateral ventral nucleus-supplementary motor area" pathway activity changes after exhaustive exercise, and discuss the basal ganglion role in central fatigue mechanisms.Methods:Male Wistar rats were randomly divided into control group (CG) ,exhaustive group (EG) and intervention group (IG). Bedford load-increasing treadmill exercise protocol was used to establish rat exhaustive exercise model Self-made metal electrodes technique was used to collect local field potential (LFP) in supplementary motor area (SMA) and analyzing its original waveform, power spectral density, average percentage of total power and various bands. In the IG after microinjection gamma-aminobutyric acid receptor antagonist bicuculline (BIC) in lateral ventral nucleus (VL) ,LFP was recorded in SMA, Re-sults:!) After exhaustive exercise overall discharge frequency of LFP and energy distribution in SMA was decreased than the CX j , which means excitability of SMA decreased;2) After BIC injection in VL,the frequency of LFP in SMA increased, average total power increased significantly^ wave percentage de-creased significantly,while the proportion of 0 wave, a wave, ^ and y wave were significantly increased Conclusions: After exhaustive exercise, neuron activity in SMA were less excitability and inhibited the “ VL-SMA” pathway activity,while BIC can reverse such phenomenoru