纳米硫化镉与硫化镉雄性生殖毒性及相关机制的研究

目的： 探讨纳米硫化镉(Nano-CdS)和硫化镉(CdS)的雄性生殖毒性作用机制并比较其生殖毒性效应。方法：将36只SPF级雄性ICR小鼠随机分为对照组、Nano-CdS组和CdS组，每组各12只。两个染毒组经口灌胃染毒，每天灌胃1次，染毒剂量均为50 mg/kg，对照组给予等体积的生理盐水，连续45 d。采用石墨炉原子吸收光谱法检测小鼠睾丸组织中镉元素积累水平，显微镜下观察小鼠精子畸形率，采用酶联免疫吸附法(ELISA)检测小鼠血清睾酮水平，采用荧光实时定量PCR检测P450scc和P450-17α mRNA表达水平。结果：镉元素含量分析结果显示，Nano-CdS和CdS组小鼠睾丸组织中的镉元素含量分别为(425.46±73.89)和(183.59±32.46) ng/g，均高于对照组的(80.18±13.29) ng/g (P<0.05)。精子畸形率检测结果显示，CdS组小鼠(2.28%)显著高于对照组(1.48%) (P<0.05)，Nano-CdS组(1.73%)也有所升高。ELISA检测结果显示，Nano-CdS和CdS组小鼠血清睾酮浓度分别为(12.31± 1.10)和(15.88±5.41)ng/dL，均明显低于对照组的(68.41±11.36) ng/dL(P<0.05)。荧光实时定量PCR检测结果显示，Nano-CdS和CdS组P450scc mRNA的表达水平分别为0.50±0.11和0.84±0.48；P450-17α mRNA的表达水平分别为0.51±0.13和0.72±0.06，除CdS组P450scc mRNA表达水平外，其他各组均明显低于对照组(P<0.05)。结论：Nano-CdS和CdS均能导致小鼠睾丸中镉元素的积累，一定程度上诱导精子畸形率的升高，并能显著降低血清睾酮水平以及抑制P450scc和P450-17α mRNA的表达水平。

Study on the toxicity and related machanisms of Nano-CdS and CdS on male reproduction

OBJECTIVE：To compare the effects of normal cadmium sulfide （CdS） and Nano-CdS on the male reproductive system of mice,and to investigate the mechanisms of reproductive toxicity. METHODS：36 male ICR mice were randomly divided into control group,and two experimental groups which were exposed to 50 mg/kg Nano-CdS and CdS,respectively. Mice in control group were exposed to same volume of physiological saline . After 45 days,levels of cadmium accumulation in testis were determined directly by GF AAS. The rate of sperm abnormality was also calculated. Serum testosterone levels were measured by enzyme-linked immunosorbent assay （ELISA）,expression levels of P450scc and P450-17α mRNA were determined by real-time PCR. RESULTS：Contents of cadmium in Nano-CdS and CdS groups were （425.46±73.89） and （183.59±32.46） ng/g,respectively,and were higher than the control （80.18±13.29） （P〈0.05）. Sperm deformity rate in CdS group （2.28%） was significantly higher than the control （1.48%） （P〈0.05）,Nano-CdS group （1.73%） was also increased. Concentrations of testosterone in CdS and Nano-CdS groups were（12.31±1.10） and （15.88±5.41） ng/dL,respectively,and were significantly lower than control group （68.41±11.36） ng/dL （P〈0.05）. Expression levels of P450scc mRNA in Nano-CdS and CdS groups were （0.50±0.11） and （0.84±0.48）,respectively, expression levels of P450-17αmRNA were （0.51±0.13） and （0.72±0.06）,respectively. Except P450scc mRNA in CdS group,the mRNA expression levels in experimental groups were significantly lower than control group （P〈0.05）. CONCLUSION：Content of cadmium accumulation in testis and sperm deformity rate were increased by exposure to Nano-CdS and CdS,with a significant reduction in serum testosterone levels and expression levels of P450scc and P450-17αmRNA.