氰戊菊酯宫内暴露对雄性仔鼠性分化的影响

Effects of maternal fenvalerate exposure on sexual differentiation of male offspring rats

目的观察氰戊菊酯宫内暴露对雄性仔鼠性分化的影响。方法将40只SD妊娠大鼠随机分为3个氰戊菊酯染毒组（分别给予2、10和50 mg/kg氰戊菊酯,于妊娠12~18 d进行灌胃染毒）和对照组（给予玉米油）。于出生第2天,测定所有仔鼠的出生体质量。每组随机选取25只雄性仔鼠,于出生第4、8、12、16、20、24、28天测体质量和肛门-生殖器间距;于出生后30 d处死,计算睾丸脏器系数。结果各染毒组仔鼠出生体质量与对照组比较,差异均无统计学意义（P〉0.05）。2 mg/kg氰戊菊酯染毒组雄性仔鼠出生后第8、12、16天时的体质量明显大于对照组（P〈0.05）;50 mg/kg氰戊菊酯染毒组雄性仔鼠第28天时的体质量明显小于对照组（P〈0.01）。出生后第4、8、12天,各染毒组雄性仔鼠肛门-生殖器间距均短于对照组（P〈0.05或P〈0.01）;至出生后第24、28天,各染毒组雄性仔鼠肛门-生殖器间距与对照组比较,差异无统计学意义（P〉0.05）。10 mg/kg、50 mg/kg氰戊菊酯染毒组雄性仔鼠睾丸脏器系数明显低于对照组（P〈0.05）。结论氰戊菊酯宫内暴露对雄性仔鼠性分化有一定影响,可导致出生早期雄性仔鼠肛门-生殖器间距缩短。

Objective To investigate the effects of maternal fenvalerate exposure on sexual differentiation of male offspring rats. Methods Forty pregnant SD rats were randomly divided into three fenvalerate groups（treated with 2,10 and 50 mg/kg fenvalerate respectively on day 12 to 18 of gestation by means of intragastric injection） and control group（treated with corn oil）.The birth weight of all male and female offspring rats were measured on postnatal day 2.The body weight and anogenital distance of 25 male offspring rats randomly selected from each group were measured on postnatal day 4,8,12,16,20,24 and 28.These 25 male offspring rats in each group were sacrificed on postnatal day 30,and organ coefficients of testis were calculated. Results There was no significant difference in birth weight of offspring rats between control group and fenvalerate groups（P〈0.05）.The body weight of male offspring rats in 2 mg/kg fenvalerate group was significantly higher than that of control group on postnatal day 8,12 and 16（P〈0.05）,and the body weight of male offspring rats in 50 mg/kg fenvalerate group was significantly lower than that of control group on postnatal day 28（P〈0.01）.The anogenital distance in fenvalerate groups was significantly shorter than that in control group on postnatal day 4,8,and 12（P〈0.05 or P〈0.01）,while there was no significant difference in anogenital distance between fenvalerate groups and control group on postnatal day 24 and 28（P〉0.05）.The organ coefficients of testis in 10 mg/kg and 50 mg/kg fenvalerate groups were significantly lower than that of control group（P〈0.05）. Conclusion Maternal exposure to fenvalerate has definite effects on sexual differentiation of male offspring rats,which can shorten anogenital distance of male offspring rats in early stage after birth.