耐力训练和益气补肾中药对睾酮合成的调节因素——StAR蛋白和P450_(SCC)酶mRNA表达的影响

Effects of Endurance Training and Chinese Medicine Compound for Invigorating Qi and Tonifying the Kidney on Testicular StAR and P450_(SCC) mRNA Levels in Rats

目的 :探讨运动训练和益气补肾中药对影响睾酮合成的StAR蛋白和P4 5 0 SCC酶的作用。方法 :5 0只雄性Wistar大鼠随机分为安静对照组 (n =1 0 )、安静服药组 (n =1 0 )、耐力训练组 (n =1 5 )和训练服药组 (n =1 5 )。经 6周递增负荷游泳训练后 ,采用放免法测定大鼠血清睾酮水平 ,利用RT -PCR方法检测大鼠睾丸StAR和P4 5 0 SCC mRNA的表达水平。结果 :(1 )训练组大鼠血清睾酮水平显著降低 ,而训练服药组大鼠的血清睾酮水平则未降低。 (2 )未服药训练大鼠的StARmRNA水平比安静对照组明显下降 (P <0 0 1 ) ;服用中药的安静大鼠和运动大鼠的StARmRNA表达比安静对照组和训练组显著增强 (P均小于 0 .0 0 1 )。 (3)训练组和训练服药组大鼠P4 5 0 SCC mRNA水平均显著低于安静对照组和安静服药组 (P <0 0 5 )。结论 :(1 )研究结果提示长期大负荷训练后大鼠睾丸间质细胞StARmRNA表达下降 ,益气补肾中药对StARmRNA的表达转录水平有增强作用。长期大负荷运动造成的血清睾酮水平下降与StARmRNA的表达强弱有关。 (2 )长期大负荷运动可造成大鼠睾酮合成限速酶P4 5 0 SCC mRNA表达降低 ,益气补肾中药可维持血清睾酮水平 ,但其在mRNA水平对P4 5 0 SCC的表达无明显效应 ,其对睾酮合成酶的影响仍需进一步探讨。

Objective Effects of exercise training and Chinese Medicine Compound for Invigorating Qi and Tonifying the Kidney on testicular StAR and P450 SCC mRNA expression in rats were observed. Methods 50 Wistar rats were randomly divided into 4 groups: sedentary control group(SC, n=10), sedentary with medicine group (SM,n=10), training group(T, n=15) and training with medicine group(TM, n=15). After 6 weeks swimming training , serum testosterone level of rats were tested through radioimmunological method; using RT-PCR, we measured testicular StAR and P450 SCC mRNA levels of rats. Results (1) In T group, serum testosterone level was lower than that in SM and TM groups. Whereas, compared with SC group, the serum testosterone level in TM group kept steadiness. (2) In T group, the gene expression of StAR was markedly lower than that in SC control (P<0.01), but the ratios of StAR/β-actin mRNA of SM and TM groups were increased evidently than that in SC group (P<0.001) and T group (P<0.001). (3)With or without Chinese medicine administration, the gene expressions of P450 SCC mRNA in training groups were markedly decreased than that of sedentary groups. Conclusion The results indicated that the reduction of StAR and P450 SCC gene expressions at mRNA level might be responsible for the low-level serum testosterone after long-term intensive exercise. Through regulating StAR mRNA level, Chinese Medicine Compound for Invigorating Qi and Tonifying the Kidney could prevent and cure the generation of low-level serum testosterone during strenuous training, but has no effect in avoiding the lower expression of P450 SCC mRNA during strenuous training.