慢性饮水染镉对大鼠睾丸的病理学影响

Effect of chronic cadmium exposure via drinking water on pathology of the testis in rats

为了探讨慢性饮水染镉对大鼠睾丸的损伤作用,试验将30只性成熟雄性SD大鼠随机等分为5组,分别饮用Cd(Cd Cl2)浓度为0,25,50,100,200 mg/L的饮水,染毒时间为56 d,定期记录各组大鼠的体质量变化,染毒结束后宰杀大鼠,观察睾丸组织的病理变化。结果表明:与对照组相比,各染毒组大鼠体质量均低于对照组,并且当镉浓度达50 mg/L时差异显著(P<0.05),200 mg/L镉组睾丸质量极显著下降(P<0.01);用光学显微镜观察睾丸,可见50 mg/L镉组睾丸曲细精管内出现精原细胞和各级精母细胞,精子细胞发生变性、坏死,并且随着镉的浓度升高,变性、坏死程度加重。透镜电镜下观察可见睾丸中生殖细胞随着镉浓度的升高,出现染色质浓缩,胞质中线粒体肿胀,嵴突消失。说明镉能够影响雄性大鼠的生长发育,造成睾丸的病理损伤。

To investigate the damage effect of chronic cadmium exposure via drinking water on rat testis, thirty sexually mature male SD rats were equally divided into five groups. The rats in these groups drank water with five concentrations of cadmium （ CdC12 ） including 0, 25, 50, 100 and 200 mg/L for 56 days, respectively. The changes in body mass of rats in each group were recorded on a regular basis during the experi- ment, and then the pathological changes of testicular tissue from sacrificed rats were observed after the end of exposure. The results showed that in comparison with the control group, the body mass in each exposure groups was lower than that in the control group, and there was a signifi- cant difference （P 〈 0.05 ） when the concentration of cadmium reached 50 rag/L, and the testicular mass in the cadmium group of 200 mg/L was extremely significantly decreased （P 〈 0.01 ） ; denatured and necrotic spermatogonia and all levels of spermatocytes and sperm cells were observed in testicular seminiferous tubules from the cadmium group of 50 mg/L by an optical microscope, serious degeneration and necrosis was found with increase of the concentration of cadmium. Condensed chromatin, swelled cytoplasmic mitochondria, and disappeared cristae were ob- served in the testicular germ cells under the lens and electron microscope. The results indicate that cadmium can affect the growth and develop- ment of male rats, and cause the pathological injury of rat testis.