镉对大鼠肾脏和睾丸毒性的比较

大鼠饮水中给镉12wk后,检测了尿低分子蛋白(LMWP)排出量。尿碱性磷酸酶(ALP)活性,血清睾酮水平,睾丸乳酸脱氢酶同功酶(LDH-X)活性,精子计数和形态,雄鼠生育力,肾,睾丸和附睾组织镉含量,并在光镜和电镜下观察上述组织的病理变化,从生化,形态和功能改变三方面比较了大鼠肾脏和睾丸对镉的敏感性,发现尿LMWP和ALP仅在高剂量组显著增加,而血清睾酮和睾丸LDH-X在中剂量纽和低剂量纽已明显降低,说明镉对睾丸的有害作用可出现在肾脏之前。

Comparison of cadmium toxicity on kidneys and on testes of rats

In order to find out the critical organ in chronic cadmium (Cd) intoxication, the Cd toxicity on kidneys and testes was compared. 3-month-old male Sprague-Dawley rats were given 0, 15.0, 37.5 or 93.8 ppm Cd in drinking water for 12 wk. The urinary excretion of low molecular weight proteins (LMWP), activity of urinary alkaline phosphatase (ALP), serum testosterone (T) level and LDH-X activity of testes homogenates were measured. By the end of the treatmant, each male was mated to two females for the assessment of male fertility. The male rats were sacrificed; the kidneys, testes, epididymides and prostates were weighed. Cd contents were measured by AAS, and the morphological changes were examined. The sperm counts and sperm morphology were also examined. The results show that the urinary LMWP excretion and ALP activity increased only in the 93.8 ppm Cd group (P<0.05). The serum T level show significant decrease in both the 37.5 and 93.8 ppm Cd groups(P<0.05). The LDH-X activity in the testes was inhibited significantly in all the Cd treated groups (P<0.01). No significant effect on male fertility was observed. Under a light microscope, a lot of protein casts were present in the collecting tubules in the 93.8 ppm Cd group. Neither renal tubular necrosis nor glomerular changes were found. No histological changes in the testes, epididymides and prostates were observed. Under an electron microscope, ultra- structural changes were observed in both 37.5 and 93.8 ppm Cd groups, and the injury was extensive in high dose group. The injuries occurred on proximal convoluted tubule cells of the kidneys, mainly on the spermatocytes and Leydig′s cells of the testes.