目的观察不同剂量碘化钾对大鼠子代生长发育的影响。方法将断乳后1个月Wistar大鼠随机分为5组(NI、5HI、10HI、50HI、100HI),饮用不同浓度的碘水,饲养3个月后雌雄台笼,取第二代1、20、60日龄仔鼠,测量血清甲状腺激素,观察不同日龄子鼠的体重、身长、尾长、后肢长及大脑和各主要脏器的的重量的变化。结果在60日龄时,各碘过量组甲状腺激索水平呈下降趋势,100HI组呈明显甲低状态;在1日龄仔鼠,与NI组相比,各高碘组仔鼠的体重、身长、尾长、后肢长及大脑和各主要脏器的重量均元明显变化(P〉0.05),随着饲以高碘饮水时间的延长,在20日龄仔鼠和60日龄仔鼠,各高碘组与NI组相比均表现出一定程度的生长发育落后,其中以100HI组最为明显(P〈0.05)。结论碘过量会影响大鼠子代的生长发育,其机理可能与高碘所致甲状腺功能低下有关,但大鼠对高碘有极强的耐受力,当碘摄入量为正常的50倍以内时,不会影响下一代的生长发育。
Objective To observe the effects of different doses KI on physical development in filial generation of Wistar rats. Methods The rats were divided into five groups (NI, 5HI, 10HI, 50HI, 100HI) by fed with water of different level of iodine. After three months, the rats mated and their filial generations of 1 - day, 20 - day and 60 - day were observed. Results The serum thyroid hormone values were gradually decreased in iodine excess groups and were significantly hypothyroidism in 100HI group of 60 - day rats. In filial generations of 1 - day, the body weight, body height, the length of caudal and posterior limb and the weight of cerebrum and the main organs were no remarkably change among different groups. With the prolong of time, the development of filial generations of 20 - day and 60 - day were later than the normal. Conclusions Iodine excess would affect the physical development in the filial generations, and the mechanism perhaps has relative with hypothyroidism induced by iodine excess. Wistar rats have high endurance to high doses of iodine, so iodine intaking within 50HI has no effect on their physical development.