甲状腺激素缺乏对脑发育期胶质细胞影响的研究

目的探讨甲状腺激素缺乏对仔一代Wistar大鼠脑发育期星形胶质细胞和少突胶质细胞的影响。方法用5mg/L（5ppm）和15mg/L（15ppm）甲巯咪唑饮水喂养孕鼠自妊娠至仔鼠出生后第28天,检测仔鼠体内甲状腺激素（TH）水平,采用免疫组化法测定海马胶质原纤维酸性蛋白（GFAP）、髓磷脂碱性蛋白（MBP）含量,分析GFAP阳性细胞的体积密度（Vv）,面数密度（NA）和细胞质平均光密度（AOD）及MBP阳性细胞AOD,正常喂养仔鼠为对照组。结果 5ppm组和15ppm组大鼠血清TH水平均低于正常对照组,5ppm组海马CA3区GFAP阳性星形胶质细胞的NA为15.11±2.41,VV为5.27±1.41,细胞质AOD为0.202±0.009,与对照组比较均明显降低,差异有统计学意义（P〈0.05）;15ppm组海马CA3区GFAP阳性星形胶质细胞的NA、VV、细胞质AOD分别为15.03±2.23、5.11±1.53、0.089±0.010,与对照组比较,差异有统计学意义（P〈0.01）。MBP阳性少突胶质细胞的细胞质AOD在5ppm组为0.234±0.005,15ppm组为0.191±0.006,均较对照组减低,差异有统计学意义（P〈0.05或P〈0.01）。结论甲状腺激素缺乏影响仔鼠海马胶质细胞发育,减少其体积密度和面数密度。

Effect of thyroid hormone deficiency on glial cells in brain development period

Objective To investigate the effects of thyroid hormone deficiency on brain development of astrocytes and oligodendrocytes in filial generation of Wistar rats. Methods The rats were fed with 5ppm and 15ppm methimazole water from pregnancy to 28 days after birth, detected the TH levels and the expression of glial fibrillary acidic protein （GFAP） and myelin basic protein（MBP） were examined by immunohistochemistry.The volume density （Vv）, numerical density on area （NA ） and the average optical density （AOD） of GFAP-positive cells and MBP positive cells were measured,normal feeding rats as control group. Results The serum TH levels of 5ppm and 15ppm group were lower than the control group; The NA of 5ppm in hippocampal CA3 region in GFAP-positive astrocytes was 15.11 ±2.41, VV was 5.27±1.41, and the AOD was 0.202 ±0.009, compared with the control group, the difference were statistically significant （P ＆lt; 0.05）; In 15 ppm group, the NA , VV and the AOD were 15.03±2.23, 5.11±1.53, 0.089±0.010,the difference were statistically significant compared with the control group （ P ＆lt; 0.01）; The AOD of MBP positive oligodendrocytes was 0.234 ±0.005 in 5ppm group, 0.191 ±0.006 in 15ppm group, they were all decreased compared with the control group, the difference was statistically significant （P ＆lt; 0.05, P ＆lt; 0.01）. Conclusion Thyroid hormone deficiency reduce the glial cells in brain development period.