镉对大鼠睾丸的损伤及锌保护作用的超微结构研究

ULTRASTRUCTURAL STUDIES OF THE INJURIOUS ACTION OF CADMIUM AND PROTECTIVE ACTION OF ZINC ON RAT TESTIS

本文报道镉所致大鼠睾丸的即刻和延迟影响以及锌对抗镉损伤的超微结构变化。将44只大鼠分为单纯镉注射组(2 mg/kg体重)、镉和锌联合注射组(锌80 mg/kg体重),以及用生理盐水注射的对照组。注射镉后10~30分钟,部分精子细胞、精原细胞、初级精母细胞和曲细精管周组织,已出现超微结构改变;其中早期精子细胞和初级精母细胞损伤出现最早。睾丸毛细血管在1小时后才查见损伤改变。间质细胞的改变则在2~4小时后见到。3~7天后,生精上皮、曲细精管周组织和睾丸间质已普遍坏死。提示镉的损伤作用,包括对曲细精管的直接损伤和对睾丸血管的直接损伤两个方面,且血管损伤出现较晚。锌对于镉损伤的保护作用显著。但是对于早期精子细胞的保护作用,较其他各级生精细胞差些。

This paper presents the ultrastructural studies of the immediate and delayed effects of Cadmium(Cd)on rat testes and the protective effects of Zinc(Zn)on Cd induced injury.Forty-two rats were divided into three groups:1)treatment with Cd(2mg/kg body weight);2)treatment with Cd combined with Zn(80mg/kg body weight);and 3)the controls.The ultrastructural changes of some spermatids,spermatogonia primary spermatocytes and peritubular tissue were detected within 10—30 minutes after Cd treatment.The morphlogical alterations of spermatids and primary spermatocytes appeared first.However,after 1 hour,the changes of testicular capillaries were observed,and those of the Leydig cells were found within 2—4 hours.After 3—7 days,the seminiferous epitheium,peritubular tissue and interstitial tissue were totally necrosed.These results suggest that both seminiferous tubules and testicular capillaries are damaged directly by Cd treatment,but the ultrastructural alterations of the capillaries appear later than those of the seminiferous tubules.The protective effect of Zn on the testicular injury induced by Cd is prominent.However,this effect on the early spermatids is weaker than that on the other germ cells.