5周间歇性负重游泳训练对大鼠睾丸Leydig细胞胆固醇代谢的影响

Effects of Five-week Intermittent Swimming on the Cholesterol Metabolism in Leydig Cells of Rat

采用实时荧光定量PCR的Taqman技术探讨5周间歇性负重游泳训练导致大鼠血清睾酮水平降低时,大鼠睾丸Leydig细胞胆固醇代谢关键环节上的HMG-CoA还原酶、LDL-R、SR-BI、类固醇激素合成急性调控蛋白(StAR)基因表达的变化。结果显示,运动引起血清睾酮显著降低时(P<0.01),Leydig细胞内LDL-R mRNA表达量显著增加(P<0.05),HMG-CoA还原酶、SR-BI、StAR mRNA表达量无显著性变化。结果表明当大鼠以负重5%体重的负荷强度进行5周的间歇性游泳训练引起血清睾酮显著降低时,Leydig细胞通过LDL-R介导的内吞作用摄取外源性胆固醇作用加强,Leydig细胞内胆固醇的合成、摄取和转运的关键环节未发生障碍。

The gene expressions of HMG- CoA reductase, LDL- R, SR- BI and StAR in Leydig cells of rats forced to swim with the load of 5 % body weight for 5 weeks were detected using the Taqman technique of real - time fluorescence quantitative PCR. With the significantly decreasing of serum testosterone caused by the swimming, the mRNA level of LDL- R increase significantly and the gene expression of HMG - CoA reductase, SR- BI and StAR in Leydig cells remain unchanged. The result suggests that when serum testosterone decrease appears after five - weeks intermittent swimming with the load of 5 % body weight, the ability to intake cholesterol is strengthened firstly by the encytosis of LDL - R in Leydig cells, and the rats with lower serum testosterone have no trouble in the key processes of the cholesterol biosynthesis, intaking and transporting in Leydig cells.