有机磷杀虫剂毒死蜱引起大鼠低温的性别差异与性腺的关系

Sexual differences of organophosphate pesticide chlorpyrifos-induced hypothermia in the rat and the relationship with gonadal function

目的研究有机磷杀虫剂毒死蜱(CHP)引起雄性和雌性大鼠低温反应与性腺的关系。方法用数字体温计测量大鼠的结肠温度,每次间隔90min,观察切除性腺对CHP引起雄性和雌性大鼠低温的影响。性腺切除和模拟手术大鼠均在术后50d进行实验。结果①给正常大鼠有机磷杀虫剂CHP可以使雄性和雌性大鼠的体温快速降低,最大低温效应在给药3h后,给药12h后结肠温度恢复到基线水平。②正常雌性大鼠对CHP的低温反应比雄性更敏感。③切除睾丸的雄性大鼠对CHP的低温反应较模拟手术大鼠明显增加,而且在给药12h后结肠温度也未恢复到基线水平。切除卵巢的雌性大鼠对CHP的低温反应与模拟手术组相似。结论雄性大鼠和雌性大鼠对有机磷杀虫剂CHP敏感性的差异主要取决于睾丸的功能。

Objective To examine sexual differences in organophosphate pesticide chlorpyrifos （CHP） - induced hypothennia in the rat and the relationship with gonadal function, Methods Colonic temperature was measured at 90 min intervals with digital thermometer.Effects of the gonadectomy on organophosphate pesticide CHP- induced hypothennia were observed in male and female rats. Gonadectomy and sham rats were administered soman 50 days after surgery, Results （1）The rats dosed with the CHP led to a rapid drop of core temperature of male and female rats, maximal hypothermia reached at 3 h after dosing. Colonic temperature recovered toward baseline core temperature at 12 h after the CHP, （2） Females were more sensitive than males to the hypothennia effects of the CHP. （3） Castrated rats administered CHP underwent a significantly longer hypothennic response, compared with sham operated controls, core temperature did not recover over 12 h.Ovariectomized female rats responding to CHP was similar to the sham operated controls.Conclusion The gonadectomy experiments suggest that sexual differences in sensitivity to chlorpyrifos in male and female rats may attribute to testicular function.