甾体激素保护睾丸生精功能免受化疗损伤的作用机理

Protection from Procarbazine Induced Testicular Toxicity by Gonadal Steroid Hormones

成熟雄性ＬＢＮＦ１大鼠皮下分别植入胆固醇（对照）和睾丸酮＋１７β雌二醇（实验组）硅胶管６周，然后腹腔注射ｐｒｏｃａｒｂａｚｉｎｅ（ＰＣＺ）。注射后２４ｈ移去上述硅胶管，９周后处死动物取材，结果睾丸重量、超声波处理的睾丸内精子头部计数、定量睾丸组织学检查均显示甾体激素对由ＰＣＺ毒性所引起的生精上皮损伤有明显的保护作用，但对体重下降及淋巴细胞减少无保护作用。甾体激素主要通过作用于未分化的精原细胞而起保护作用。

To confirm the claims that the procarbazines(PCZ)effect on stem spermatogonia can beovercome by gonadal steroid hormones ,mature , LBNF1 male rats were implanted with silastic capsules containing testosterone(T 200 mm)+estradiol(E 50 mm).The silastic capsules of control and TE groups were removed 24 hours after the PCZ injection and the rats weresacrificed 9 weeks later. The functional status of the testis and the hormonal parameters at the time of injection of PCZ were measured and correlated with the degree of protection,asmeasured by the recovery of sperm counts.The results indicated that testosterone and estradiol does protect spermatogenesis from PCZ intoxification. To determine whether the protection is specific for stem spermatogonia,we also measured body weight loss 3-4 days,lymphocyte counts l day, and spermatocyte count 9 days after PCZ treatment. There were no differences in the dose response curves of these three assays between the hormone and shamtreated rats. The lack of protection indicates that the hormonal protection of stem spermatogonia was not due to the alterations in either systemic or testicular pharmacokinetics of spermatocyte. We conclude that A3 spermatogonia and preleptotene spermatocyte are sensitive toPCZ and there is no evidence of hormonal protection for the differentiated spermatogonia andpreleptotene spermatocyte.