Effects of mixed exposure to low-dose chlorpyrifos and cypermethrin on reproductive function in female rats
YANG Chao-ju1, WANG Shu-song2
1.Hebei General Hospital, Shijiazhuang, Hebei 050051, China; 2.Key Laboratory of Family Planning & Health Birth, National Health & Family Planning Commission, Hebei Family Planning Science & Technology Research Institute, Shijiazhuang, Hebei 050051, China
Abstract：Objective To observe the effects of mixed exposure to low-dose chlorpyrifos and cypermethrin on reproductive function in female rats. Methods Female and male healthy Wistar rats were mixed in a 2:1 ratio in the cage. The pregnant rats were divided into the control group, the chlorpyrifos group, the cypermethrin group and the chlorpyrifos and cypermethrin group (each n=8). Gastric perfusion was performed according to the weight of the 1 ml/kg calculation. The chlorpyrifos group, the cypermethrin group and the chlorpyrifos and cypermethrin group were given chlorpyrifos 1.6 mg/kg, cypermethrin 2.5 mg/kg and chlorpyrifos 1.6 mg/kg combined with cypermethrin 2.5 mg/kg from gestation day 1 to 8 respectively by gavage. All pregnant rats were sacrificed on the 19th day of pregnancy. The number of ovulated corpus luteum, the total number of implantation, and the weight and length of live fetuses were recorded, and surface deformity of live fetuses was observed. The placentae were separated, and the weight of placentae was recorded. Acetylcholinesterase (AchE) activity in rat whole blood was detected, and P450aromA was detected by immune histochemical method. Results On the 19th day of pregnancy, body mass of pregnant rats in the chlorpyrifos and cypermethrin group was decreased obviously as compared with that of the control group (P<0.05). No statistically significant differences were observed in the number of ovulated corpus luteum, the total number of implantation, stillbirth rate, sex ratio of fetuses and length of fetuses between each exposure group and the control group (P>0.05). The weight of placentae was significantly lower in the chlorpyrifos and cypermethrin group than in the control group (P<0.05). Body mass of live fetuses in each exposure group was decreased significantly as compared with that of the control group (P<0.05). AchE activity in whole blood of pregnant rats in the chlorpyrifos and cypermethrin group was significantly reduced than that in the control group (P<0.05). P450aromA protein expression in placentae in the chlorpyrifos group and the cypermethrin group was similar to that in the control group (P<0.05), while P450aromA protein expression in placentae in the chlorpyrifos and cypermethrin group was significantly higher than that in the control group (P<0.05). Conclusions Mixed exposure to low-dose chlorpyrifos and cypermethrin in female rats produces certain embryo toxicity, and results in the delayed development of offspring, the decreased AchE activity in pregnant rats and the enhanced expression of P450aromA protein in placentae.
杨朝菊, 王树松. 低剂量毒死蜱和氯氰菊酯联合染毒对雌性大鼠生殖发育的影响[J]. 实用预防医学, 2019, 26(2): 173-175.
YANG Chao-ju, WANG Shu-song. Effects of mixed exposure to low-dose chlorpyrifos and cypermethrin on reproductive function in female rats. , 2019, 26(2): 173-175.
2019, Vol. 26 
