高碘对仔鼠脑甲状腺激素的影响及硒的干预作用

目的研究高碘摄入对小鼠仔鼠脑组织甲状腺激素的影响及硒的干预作用。方法将60只Balb/c小鼠随机分为4个不同的饮水组:正常对照组、高碘组(3000μg/L)、单独补硒组(200μg/L)、高碘加硒组(I3000μg/L+Se200μg/L)。喂养4个月时,雌雄交配。测定14和28日龄仔鼠血清TSH和甲状腺激素水平以及0、14和28日龄仔鼠大脑组织甲状腺激素水平。结果14日龄仔鼠高碘组血清TT4水平显著低于对照组和高碘加硒组,而TSH水平显著高于对照组和高碘加硒组(P<0·05),高碘组0和14日龄仔鼠脑组织甲状腺激素含量显著低于对照组、单独补硒组和高碘补硒组(P<0·05),28日龄仔鼠血清和脑组织甲状腺激素含量各组间差异无统计学意义。结论补硒能缓解高碘所致仔鼠脑组织甲状腺激素的改变。

Influences of excess iodine on thyroid hormone concentrations in cerebrum of filial mice and intervention of selenium

OBJECTIVE: To study the influence of excessive iodine intake on thyroid hormones in cerebrum of filial mice and intervention of selenium. METHODS: 60 Balb/c mice were divided randomly into 4 groups: control group, iodine group, selenium group and iodine plus selenium group and given tape water, tape water containing iodine 3000 microg/L, tape water containing selenium 200 microg/L and tape water containing iodine plus selenium 200 microg/L respectively as drinking water. At the end of the fourth month, the mice mated. Thyroid hormones and TSH in serum and in cerebrum of filial mice were determined at the postnatal 0, 14th and 28th day. RESULTS: At the postnatal 14th day, serum TT4 level was lower significantly, and serum TSH was higher in iodine group than those in control group and in the iodine plus selenium group. At the postnatal 0 day and 14th day, thyroid hormone concentrations in the cerebrum of progeny of mice were lower significantly in iodine group than those in control group, selenium group and iodine plus selenium (P < 0.05). No significant difference was observed among the four groups in TT4, TT3 and rT3 concentrations in serum and cerebrum at the postnatal 28th day. CONCLUSION: Excessive iodine intake can change thyroid hormone concentrations in the cerebrum of progeny of mice and selenium supplementation exerted favorable effects on it.