“黑质/苍白球-丘脑-皮质”通路5-羟色胺1B受体及多巴胺1型受体在大鼠运动疲劳调控中的作用

摘要

Objective:To observe the changes of 5-HT1B and D1DR expression in nucleus of "SNr/GPi-VL-SMA" pathway in pre and post-exhaustive exercise,and investigate the central mechanism of "SNr/GPi-VL-SMA" pathway modulating the occurrence and development of exercise-induced fatigue.Method:Twenty-four male Wistar rats were randomly divided into control group (CG),immediately after exhaustion group (EG),and 90min after recovery group (RG),each consists of 8 rats.The expression level of 5-HT1B and D1DR receptors in each group were observed with the immunohistochemistry technique.Result:Compared with CG,the positive cell area/scanning area value (R value) and the average optical density value (AOD value) of 5-HT1B receptor in SNr and GPi of the EG and RG rats both decreased significantly (P ＜ 0.05),while the R value and AOD value of D1DR both increased significantly(P＜ 0.05).The R value and AOD value of 5-HT1B receptor in VL of EG and RG rats increased significantly(P＜0.05,P＜0.01).In SMA,the R value and AOD value of 5-HT1B receptor of EG and RG rats increased significantly (P＜ 0.05),while,the R value and AOD value of D1DR receptor decreased significantly (P ＜ 0.05).Conclusion:Changes of 5-HT1B receptor and D1DR receptor expression in the nuclei of ‘SNr/GPi-VL-SMA'pathway caused the changes of the neurotransmitters release,thus affecting the excitability of the electrical activity of neurons,this might be one of the important ways for ‘SNr/GPi-VL-SMA'pathway modulating the exercise-induced fatigue and exercise performance.%目的:通过观察运动大鼠力竭前后“黑质/苍白球-丘脑-皮质”通路各核团5-羟色胺1B受体(5-HT1B)及多巴胺1型受体(D1DR)的蛋白表达水平,探讨“黑质/苍白球-丘脑-皮质”通路调控运动疲劳发生、发展的中枢机制.方法:24只雄性Wistar大鼠,随机分为安静对照组、力竭即刻组、恢复90min组,每组8只.采用免疫组织化学技术对不同组别5-HT1B和D1DR的蛋白表达水平进行检测.结果:与安静组对照组相比,力竭即刻组、恢复90min组大鼠黑质网状部及苍白球内侧部5-HT1B受体阳性细胞R值及平均光密度(AOD)值均显著减少(P＜0.05),D1DR受体阳性细胞R值及AOD值均显著增加(P＜0.05);力竭即刻组、恢复90min组大鼠丘脑腹外侧核5-HT1B受体阳性细胞R值及AOD值均显著增加(P＜ 0.05,P＜0.01);在大鼠皮质辅助运动区,力竭即刻组、恢复90min组5-HT1B受体阳性细胞R值及AOD值均显著增加(P＜0.05),D1DR受体阳性细胞R值及AOD值均显著减少(P＜ 0.05).结论:力竭运动过程中“黑质网状部/苍白球内侧部-丘脑-皮质”各核团5-HT1B及D1DR受体蛋白表达变化引起神经递质释放量改变,进而影响神经元电活动兴奋性,可能是“黑质网状部/苍白球内侧部-丘脑-皮质”通路调节运动疲劳及运动能力的重要途径之一.