1周速度训练对大鼠骨骼肌PHGPx基因表达的影响

目的 :采用RT -PCR技术测定和分析不同类型骨骼肌中谷胱甘肽磷脂氢过氧化物酶(PHGPx)基因表达水平以及速度训练前后PHGPx基因的表达 ,以探讨PHGPx在骨骼肌抗氧化体系中的作用。方法 :雄性SD大鼠 2 0只 ,随机分为训练组 (T ,n =10 )和对照组 (C ,n =10 )。在动物跑台上进行为期 1周的速度训练 ,采用RT -PCR方法测定比目鱼肌、腓肠肌红肌和白肌PHGPxmRNA含量。结果 :对照组腓肠肌红肌和白肌PHGPx基因表达无显著差异 ,但均显著高于比目鱼肌 (P <0 0 5 ) ;1周速度训练后腓肠肌白肌PHGPx基因表达增加 (P <0 0 5 ) ,红肌PHGPx基因表达下降 (P<0 0 5 )。结论 :PHGPx基因表达水平存在肌纤维类型特异性 ,IIa和IIb型肌纤维中的基因表达高于I型肌纤维 ;腓肠肌PHGPx基因表达水平受运动训练的调节 ,速度训练使PHGPx基因在Ⅱb型肌纤维中表达升高 ,而在Ⅱa型肌纤维中表达降低。

Effect of Sprint Exercise on PHGPx Gene Expression in Skeletal Muscle of Rats

Objective To study the role of PHGPx in the antioxidant system of skeletal muscle, the effects of fiber type and sprint exercise on gene expression of PHGPx in skeletal muscle were observed by RT-PCR. Methods Twenty adult male SD rats were randomly divided into two groups: training group (T,n=10), control group (C,n=10). T group was subjected a seven-day sprinting training program on motor-driven treadmill. The level of PHGPx mRNA was determined in the soleus(So), gastrocnemius red fiber(GR)and gastrocnemius white fiber(GW). Results The level of PHGPx mRNA in GR and GW was not significantly different in the control group, but higher in So(P<0.05) After the training program, the level of PHGPx mRNA in GW was increased significantly(P<0.05), the level of PHGPx mRNA in GR was decreased(P<0.05). Conclusion These data demonstrate that level of PHGPx gene expression varies in accordance to the muscle fiber type, and exercise training-induced changes in muscle fiber PHPGx gene expression are muscle fiber specific.