孕期碘营养状态对子代大鼠成骨细胞的影响

目的 观察孕期碘营养状态的改变对大鼠仔鼠成骨细胞的的影响。方法 雌性 Wistar大鼠，交配妊娠后，取孕鼠 20 只按体重随机分成对照Ⅰ组，对照Ⅱ组，碘缺乏组，碘过量组。自妊娠日起，对照Ⅰ组饲以普通饲料+去离子水，对照Ⅱ组饲以缺碘饲料+适碘去离子水，碘缺乏组饲以缺碘饲料+去离子水，碘过量组饲以普通饲料+高碘水。孕18日时，检测各组孕鼠甲状腺激素和促甲状腺激素水平；仔鼠出生后，取出生24小时内仔鼠的颅骨成骨细胞进行培养，观察成骨细胞碱性磷酸酶活性和细胞增殖能力。 结果 碘缺乏组甲状腺激素含量较对照Ⅰ组、对照Ⅱ组和碘过量组明显降低（均P<0.05），促甲状腺激素含量则明显升高（均P<0.05）；碘过量组甲状腺激素含量与对照Ⅰ组和对照Ⅱ组间差别没有统计学意义（均P>0.05），但促甲状腺激素含量则明显升高（均P<0.05）。碘缺乏组成骨细胞碱性磷酸酶活性和细胞增殖能力较对照Ⅰ组、对照Ⅱ组和碘过量组明显下降（均P<0.05）。 结论 大鼠孕期碘营养状态不足，可导致新生仔鼠成骨细胞活性和增殖能力下降，这为进一步探讨其对牙齿发育矿化的研究提供了实验依据。

Effects of iodine on osteoblasts in pup rats

Objective To study the effects ofiodine onosteoblasts in pup rats. Methods Female Wistar rats（n = 20） after pregnan- cy were randomly divided into four groups：control group Ⅰ ,control group Ⅱ ,iodine deficient group,iodine overdose group. The control group I was fed with a normal diet and drank deionized water,while the control group H was fed with an iodine-deficient diet and drank deionized water with adequate iodine during the experiment. The iodine deficient group was fed with an iodine-deficient diet and drank deionized water during the experiment,while the iodine overdose group was fed with a normal diet and drank deionized water with high iodine. On gestational day 18, the levels of thyroid hormones and thyroid stimulating hormone were tested in pregnant rats. On post- natal day 0, alkalinephosphatase activities and proliferation of osteoblasts were observed in pup rats. Results The levels of thyroid hor- mones in iodine deficient group were significant lower than the controls （ all P 〈 0.05 ） , while the levels of thyroid stimulating hormone increased significantly（ all P 〈 0.05）. There were no significant differences in the levels of thyroid hormones between the iodine over- dose group and the controls（ all P 〉 0.05 ）. However,a significant up-regulation of thyroid stimulating hormone was observed in the io- dine overdose group compared to the controls （ all P 〈 0.05 ）. The alkalinephosphatase activities and proliferation of osteoblasts were sig- nificantly down-regulated in iodine deficient group compared to other groups（ all P 〈 0.05 ）. Conclusions Iodine deficiency in preg- nant rats led to down-regulation of alkalinephosphatase activities and proliferation of osteoblasts inpup rats.