PFOS青春期暴露对成年期雄性大鼠的生殖毒性

为探究青春期的PFOS暴露对成年后的SD大鼠的生殖毒性,对出生后第21天(PND21)的SD大鼠经口灌胃不同剂量的PFOS(5、10和20mg·kg~(-1)),连续染毒7d,在出生后第56天(PND56)时,对各染毒组SD大鼠的体质量、精子数量、血清中的睾酮浓度,以及睾丸间质细胞睾酮合成的相关基因mRNA水平进行了检测。结果显示,10mg·kg~(-1)剂量组大鼠体质量较对照组明显下降(P<0.01);精子数量在10mg·kg~(-1)和20mg·kg~(-1)剂量组明显降低(P<0.05);血清中睾酮浓度随着PFOS剂量的加大有明显下降的趋势,20mg·kg~(-1)剂量组显著低于对照组(P<0.05);类/胆固醇相关基因star和cyp11α1的mRNA表达水平明显下调。研究表明,青春期的PFOS暴露会导致睾酮合成途径中相关因子的功能缺失,破坏成熟睾丸间质细胞的功能,致使睾酮水平降低,并抑制精子生成,从而破坏生殖系统的功能。

Reproductive Toxicity of PFOS Adolescent Exposure to Adult Male Rats

To explore the reproductive toxic effect of adolescent exposure to perfluorooctane sulfonate(PFOS) on adult male rats,the adolescent SD rats on postnatal day 21(PND21) were exposed to different doses of PFOS(5,10 and 20 mg·kg~(-1)) by gavage for 7 days.Several indexes of SD rats on PND56 in each exposure group were measured,including body mass,sperm count,serum testosterone concentration,and mature Leydig cell mRNA levels associated with testosterone synthesis.Results indicated that compared with the control,the body mass of rats significantly decreased in 10 mg·kg~(-1) exposure group(P< 0.01);sperm counts were significantly lower in 10 mg·kg~(-1) and 20 mg·kg~(-1) exposure groups(P< 0.05);serum testosterone concentration exhibited a clear decreasing pattern with increasing PFOS dose,and the concentration was significantly lower in 20 mg·kg~(-1) exposure group(P< 0.05);the mRNA levels of steroid/cholesterol-related genes,star and cyp11α 1,significantly decreased.It is demonstrated that PFOS adolescent exposure would cause the loss of function related to testosterone synthesis,thus resulting in destroying mature Leydig cell function,reducing the testosterone concentration in SD rats and inhibiting sperm production,and finally destroy the function of reproductive system.