环磷酰胺对睾丸组织端粒酶活性表达的影响及意义

目的通过环磷酰胺对大鼠睾丸组织中端粒酶活性影响的研究,探讨端粒酶活性在环磷酰胺导致生精功能损害中的意义。方法选取9d龄雄性Wistar大鼠,给予大、中、小剂量环磷酰胺后24h、4周、8周分别采集睾丸标本,采用TRAP-ELISA法检测睾丸组织中端粒酶活性的变化。结果①用药后24h、4周、8周,各实验组睾丸组织中端粒酶活性均较对照组显著降低(P<0.01);②随时间的增加,对照组虽有逐渐下降趋势,但各时段差异无显著性意义(P>0.05),而各实验组不但有明显的下降,且4周、8周较24h有显著降低(P<0.01);③各实验组同一时期比较,端粒酶活性均随CTX剂量增加而逐渐下降,其中,大、中剂量组与小剂量组比较均显著降低(P<0.01),CTX剂量与端粒酶活性负相关。结论环磷酰胺在损害生精功能的同时,也诱导睾丸组织端粒酶活性下调,并与剂量负相关,且有明显远期效应,提示环磷酰胺所致睾丸生精功能损害可能与其端粒酶活性持续性降低有关。

The effect of cytoxan on the change of telomerase activity of the testes in rats

Objective To assess the effect of cytoxan on the change of telomerase activity of the testes in young rats.Methods Different doses of cytoxan were injected to the 9 days male Wistar rats. The testes were collected in these rats at 24 h,4 w and 8 w after injection.The telomerase activity in the testes was detected by PCR-ELISA.Results After 24 h,4 w and 8 w,telomerase activity of the testes in experimental rats was significantly lower than that of control rats (P<0.01).There were no significant difference of the telomerase activity of the testes in control rats at different time-point, while the telomerase activity of the testes at 4w and 8w was significant lower than that of 24h in exper- imental group (P<0.01).With increase of dose,telomerase activity of the testes in experimental groups was gradually decreased,and the telomerase activity in large and medium-dose groups was sig- nificantly lower than that of small-dose group(P<0.01).There was a negative correlation between the dose of cytoxan and the telomerase activity of the testes.Conclusions Cytoxan gets the telomerase activity of the testes reduced in young rats.The reduction of telomerase activity of the testes may be correlated with inpaired seminiferous function induced by cytoxan.