碘过量对仔鼠大脑锥体细胞的形态学影响

目的 探讨碘过量对Wistar大鼠仔鼠大脑锥体细胞的形态学影响。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个月后雌雄合笼，取第二代1、20、60日龄仔鼠，观察仔鼠的脑发育。结果在1日龄仔鼠中，与NI组相比，各碘过量组仔鼠锥体细胞顶树突棘突密度、棘突的分布类型、锥体细胞基树突数、初级树突分枝指数、锥体细胞的最大横截面积、体密度和面数密度均无明显变化（P〉0．05）；在20日龄仔鼠中，100HI组顶树突棘突密度、锥体细胞的最大横截面积较NI组减小（P〈0．05）；而在60日龄仔鼠中，50HI组和100HI组与NI组相比都表现出一定程度的脑发育落后，其中以100HI组最为明显（P〈0．05）。结论大鼠对碘过量有极强的耐受力，严重碘过量（正常摄人量50倍以上）会影响仔鼠大脑锥体细胞的发育，进而阻碍脑的发育。

Influence of iodine excess on cerebrum pyramidal cells in filial generation of rats

Objective To study the effects of different doses iodine excess on cerebrum pyramidal cells in filial generation of Wistar rats. Method 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. The changes of cerebral development were observed. Results In filial generations of 1 - day, the density and distributional types of spinal processes in pyramidal cells, the exponent, the maximum cross section area, the mean volume and surface of cortex pyramidal cells were no remarkabe change among different groups. In filial generations of 20 - day the density and the maximum cross section area in 100HI group reduced（ P 〈 0.05）. In filial generations of 60 - day, compared to NI group, 50HI group and 100HI group showed brain development backward, especially 100HI group（ P 〉0.05）. Conclusion Wistar rats have high endurance to high doses of iodine, iodine excess would affect the development of the pyramidal cells in the filial generations when iodine intaking above 50HI.