饮水染镉对雄性大鼠精子发生的影响

Effects of chronic cadmium exposure via drinking on spermatogenesis of male rats

通过对性成熟及性未成熟雄性大鼠进行慢性饮水染镉,探究了镉对大鼠精子发生的影响,为镉对雄性大鼠生殖毒性作用及其机理的研究奠定理论基础。将30只雄性SD大鼠(性成熟)随机等分成5组,分别饮用镉的质量浓度为0、25、50、100和200mg/L的饮水,试验期为56d;将15只雄性SD大鼠(性未成熟)随机等分成3组,分别饮用镉的质量浓度为0、50和200mg/L的饮水,试验期为105d。试验期结束后观察大鼠的附睾尾重、附睾尾中精子活力、精子活率、精子密度、精子形态等指标的变化情况。结果显示,对于性成熟大鼠,100mg/L镉剂量组与对照组相比,上述指标显著下降(P<0.05),200mg/L镉剂量组与100mg/L镉剂量组相比,上述指标极显著下降(P<0.01);100mg/L镉剂量组的精子畸形率与对照组相比,呈极显著增加(P<0.01)。对于性未成熟大鼠,50mg/L镉剂量组与对照组相比,上述指标显著下降(P<0.05),200mg/L镉剂量组与50mg/L镉剂量组相比,上述指标极显著下降(P<0.01);50mg/L镉剂量组的精子畸形率与对照组相比,极显著升高(P<0.01)。结果表明,慢性饮水染镉对动物精子的发生具有毒性作用,可明显影响雄性动物的生育功能,且存在剂量效应和时间效应关系。

Through chronic cadmium exposure via drinking,effects of cadmium toxicity on spermatogenesis were studied in sex immature and sex mature male rats,which will provide basic and theoretical proof for cadmium in reproductive toxicity in male rats and its mechanism.Thirty male SD rats(sex mature)were randomly divided into five groups.The concentrations of cadmium in drinking water of these groups were 0,25,50,100 and 200mg/L for 56 days,respectively.Fifteen male SD rats(sex immature)were randomly divided into three groups.Concentrations of cadmium in drinking water of these groups were 0,50 and 200mg/L for 105 days,respectively.After the experiments,the changes of the weight of epididymis tail,the motility of sperm,the sperm density,living sperm ratio and sperm morphology were observed.In result,the indexes above were all expressed as1 Sex mature groups:100mg/L cadmium group decreased compared with control group(P<0.05),and 200mg/L cadmium group significantly decreased compared with 100mg/L cadmium group(P<0.01).The abnormal sperm ratio of 100mg/L cadmium group significantly increased.2Sex immature groups:50mg/L cadmium group decreased compared with control group(P<0.05),and 200mg/L cadmium group was significantly decreased compared with 50mg/L cadmium group(P<0.01).The abnormal sperm ratio of 50mg/L cadmium group significantly increased.The results indicate that chronic cadmium exposure via drinking causes toxicity on spermatogenesis and can obviously affect the reproductive function of male animals,and the effect is dose-and time-dependent.