妊娠期混配农药暴露对亲子两代大鼠内分泌和免疫系统的影响

Effects on Endocrine and Immune System of Pregnant Rats and Their Offspring Exposed to Cypermethrin Plus Methylparathion During Gestation

[目的]探讨妊娠期氯氰菊酯和甲基对硫磷混配染毒对亲子两代大鼠的内分泌干扰和免疫毒性效应。[方法]孕鼠112只随机均分为4组,于妊娠第1～15天,以剂量为0(对照组)、1/300LD5(0低)、1/95LD5(0中)、1/30LD5(0高)等毒混配的氯氰菊酯和甲基对硫磷,每日灌胃染毒1次,共15天;对照组为色拉油。56只孕鼠自然分娩,仔鼠10周龄时随机抽取64只(每组16只,雌雄各半)处死;另56只孕鼠(每组14只)于妊娠19天处死;亲子两代分别称量脏器重量,用放射免疫法测定血清促卵泡成熟激素(FSH)、促黄体生成激素(LH)、雌二醇(E2)和睾酮(T);三碘甲状腺原氨酸(T3)、四碘甲状腺原氨酸(T4)和促甲状腺激素(TSH)以及免疫球蛋白IgG和IgA。[结果]脏器系数中仅仔鼠的卵巢重量系数与混配农药之间存在剂量-效应关系(rs=0.3144,P=0.0172);孕鼠中剂量组血清T3水平高于对照组(P<0.05),仔鼠低剂量组血清睾酮高于对照组(P<0.05);孕鼠IgA水平存在剂量-效应关系(rs=0.4649,P=0.0002);其余未发现异常。[结论]妊娠期氯氰菊酯和甲基对硫磷混配染毒对母鼠和子代有一定的内分泌干扰效应。

[ Objective ] To study the effects on endocrine and immune system in rats exposed to mixed cypermethrin with methylparathion during gestation. [ Methods ] 112 pregnant Wistar rats were divided randomly into 4 groups, and were force-fed once a day during 1^st to 15^th day in gestation period with equivalent doses of 0, 11300 LD50, 1/95 LD50, 1/30 LD50 of cypermethrion plus methylparathion respectively. The control group were fed with vehicle solvent only. 56 pregnant rats gave their natural dilivery. 64 offspring（ 16 in each group, including 8 females and 8 males ）at lO-weeks-old and the other 56 pregnant rats at gestation day 19th were sacrificed. Their organ/body weights were determined. Reproductive hormones, thyroid hormones and immunoglobulin such as ： luteinizing hormone （ LH ）, follicle-stimulating hormone （ FSH ）, estradiol （ E2 ）, testosterone （ T ）, triiodothyronine （ T3 ）, tetraiodothyronine （ T4 ） and thyroid-stimulating hormone （ TSH ）, together with IgG and IgA in the serum were tested using Radioimmunoassay （ RIA ）. [ Results ] It was found that ovary weight/body weight of female offspring had a dose-effect relationship（ rs=0.3144, P=0.0172 ）. Serum T3 level in middle-dose group of dam was higher than that in the controls （ P〈0.05 ）. The testosterone level in low-dose group of male offspring was higher than that in control group（ P〈0.05 ）, but no doseeffect relationship was observed（ rs=-0.112, P=0.39 ）. Anyway, a dose-effect relationship was observed in IgA level of dam（ rs= 0.4649, P=0.0002 ）. [ Conclusion ] Exposure to mixed cypermethrin with methylparathion during gestation period might affect reproductive hormones in dam and offspring of rats.