力竭运动对大鼠大脑P2X_1、P2X_3、P2X_5和P2X_7受体表达的影响

Feature of Variation in P2X_1,P2X_3,P2X_5 and P2X_7 in Rat Brain after Exhaustive Exercise

目的:探讨一次和反复力竭游泳运动后大鼠大脑ATP受体P2X之4个亚型P2X1、P2X3、P2X5和P2X7的时相性变化特点。方法:健康成年雄性SD大鼠68只,分为一次力竭游泳运动组和反复力竭游泳运动组及安静对照组。反复力竭组大鼠每日负重3%体重进行力竭游泳运动,共训练2周。运动组分别于力竭运动后即刻、4小时、12小时和24小时取材。采用实时荧光定量PCR方法测定力竭运动后大鼠P2X1、P2X3、P2X5和P2X7受体亚型mRNA水平。结果:(1)一次力竭组中,P2X1和P2X7相对表达率在运动后12小时最低,且与24小时有显著统计学差异(分别为P<0.05,P<0.01)。P2X3和P2X5相对表达率在运动后各时点只在一定范围内波动。(2)反复力竭组运动后12小时4种受体亚型相对表达率均达到峰值,较其它各时间点及安静对照组、一次力竭12小时均有显著差异(P<0.01)。结论:4种受体亚型表达率在反复力竭运动后12小时出现峰值,提示4种P2X受体亚型参与的中枢神经活动在力竭运动后12小时可能达到一个活跃期。

Objective The＇ purpose of this study is to investigate the characteristic variation in P2X1, P2X3, P2X5 and P2X7 receptors in rat brain after single bout and repeated 68 male SD rats were divided randomly into the single bout exhaustive exhausting swimming group ,and the sedentary control group. Rats in the exhaustive exercise. Methods swimming group, the repeated repeated exhaustive swimming group swam every day with weight-bearing of 3% body weight to exhaustion for two weeks. The brain tissue of the rats was taken at 0 hr,4 hr, 12 hr and 24 hr after exhaustive swimming. The mRNA levels of P2X~,P2X3,P2X5 and P2X7 receptors in the brain tissue were determined through real-time quantitative PCR method. Results （1）The relative expression rates of both P2X1 and P2X7 at 12 hours after exercise in single bout exhaustive group were minimum and significantly different from the values at 24 hours （P 〈 0.05 and P 〈 0.01 ,respectively）. The relative expression rate of P2X3 and P2X5 at each time point after the exercise fluctuated in a certain range. （2）The peak relative expression rates of the 4 receptor subtypes revealed at 12 hour after exercise in the repeated exhausting group,and were statistically different from that at other time points and from the control （P 〈 0.01）. Conclusion The peak relative expression rates of the 4 P2X receptor subtypes after the repeated exhaustive exercise revealed at 12 hr after exhaustive exercise,when they actively involved in physiological and biochemical activities of the central nervous system.