邻苯二甲酸二(2-乙基)己酯短期重复暴露对大鼠行为的影响

Behavioral changes of rats after short-term exposure to di-(2-ethyl hexyl) phthalate

目的初步探讨邻苯二甲酸二(2-乙基)己酯(DEHP)短期重复暴露对大鼠神经行为的影响。方法 SD雄性大鼠用0、150、450、1350 mg/(kg.d)DEHP连续灌胃染毒28 d。利用旷场(OFT)和高架十字迷宫(EPM)动态测试染毒前后大鼠行为学变化,并称量肝、肾和睾丸。结果染毒前各组大鼠在OFT和EPM测试中均无显著性差异。染毒组与对照组相比体质量无统计学意义(P>0.05);从染毒第3周开始,各组大鼠每周食物利用率有统计学意义(P<0.05),总食物利用率有统计学意义(P<0.01)。与对照组相比,各染毒组肝脏、睾丸脏器系数差异有统计学意义(P<0.01),肾脏脏器系数差异则无统计学意义(P>0.05),肾脏系数指标则无统计学意义(P>0.05);高剂量组与对照组OFT运动总距离有统计学意义(P<0.05);高剂量组与对照组、低、中剂量组OFT中央区活动时间均有统计学意义(P均<0.05);中央区进入次数无统计学意义(P>0.05);各组大鼠在EPM进臂总次数、开臂停留时间占总进臂时间百分比及开臂次数占总进臂次数百分比上差异均无统计学意义(P>0.05)。结论 DEHP对大鼠有一定毒性作用,影响自发活动和探索行为,使其对危险的预判能力下降,对人类可能产生潜在危害。

Objective To observe the behavioral changes of rats after subchronic exposure to di-（2-ethyl hexyl） phthalate （DEHP）. Methods Twenty-four healthy male SD rats were randomized equally into 4 groups, namely the solvent control group （sesame oil） and 3 DEHP groups with daily intragastric administration of DEHP at the doses of 150, 450, and 1350 mg/kg for 28 days. The neurobehavioral changes of rats were evaluated by open-field test （OFT） and elevated plus-maze test （EPM）, and the body weight and organ coefficients were measured. Results The rats showed no significant differences in the performance in OFT or EPM before DEHP exposure. The body weight of the rats increased with the prolonged DEHP exposure, but no significant differences were found between the treatment groups and the control group （P〉0.05）. From the third week of exposure, the weekly food consumption and the food utilization rate showed significant differences between the treatment groups and the control group （P〈0.05 and P〈0.01）, and the liver and testis coefficients, but not the kidney coefficient, also differed significantly （P〈0.01, P〈0.01, and P〉0.05）. In OFT, the total distance of movement was the longest in high dose treatment group （P〈0.05 vs control group）, and the durations of stay in the central area, but not the number of times of entry, differed significantly between the 3 treatment groups and the control group （P〈0.05 and P〉0.05）. In EPM test, however, the performances of the rats was all similar between the 4 groups （P〉0.05）. Conclusion DEHP can affect the locomotor activity and exploratory behavior of rats after short-term exposure, suggesting its possible hazard in human being.