摘要
目的分析3,3’,5-三碘甲腺原氨酸(T3)对体外培养的大鼠大脑皮层神经元G蛋白Go的α亚单位(Goα)基因表达的影响。方法取孕19 d的胚胎大鼠大脑皮层神经元,于含15％胎牛血清的DMEM培养基中培养。7 d后神经元分为5组,分别置于不同的培养基:DMEM+15％胎牛血清(A组); DMEM+15％去甲状腺激素的胎牛血清(B组);含0．5 nmol／L T3的DMEM+15％去甲状腺激素的胎牛血清(C组);含5 nmol／L T3的DMEM+15％去甲状腺激素的胎牛血清(D组);含50 nmol／L T3的DMEM+ 15％去甲状腺激素的胎牛血清(E组)。继续培养7 d,收集细胞,抽提总RNA,以竞争性RT-PCR分析各组神经元GoαmRNA水平。结果B、D和E组神经元GoαmRNA水平显著低于A组(均P<0．01);C组神经元GoαmRNA水平显著高于A、B、D和E组(P<0．01);B、D和E组之间则差异无统计学意义(P> 0．05)。结论T3对体外培养的神经元Goα基因的表达有双重调节作用:在一定浓度范围内T3对培养的神经元Goα基因的表达有下调作用;但如果培养基中缺乏T3,神经元Goα基因的表达水平也很低。甲状腺激素对神经元Goα基因表达的调节作用可能是其调节脑发育的机制之一。
Objective To investigate the effect of triiodothyronine on the expression of alpha subunit of G protein Go （Goα） gene in cultured rat cerebral cortex neurons. Methods Primary cultured neurons of rat were prepared from the cerebral cortex at embryonic day 19. The neurons were cultured in DMEM supplemented with 15% fetal calf serum. After 7 days, the neurons were cultured in different media： DMEM supplemented with 15% fetal calf serum （group A）, DMEM supplemented with 15% fetal calf serum stripped of thyroid hormone （group B）, 0.5nmol/L T3-containing DMEM supplemented with 15% fetal calf serum stripped of thyroid hormone （ group C）, 5nmol/L T3-containing DMEM supplemented with 15% fetal calf serum stripped of thyroid hormone （group D） and 50nmol/L T3-containing DMEM supplemented with 15% fetal calf serum stripped of thyroid hormone （group E）. The neurons were cultured for another 7 days and total RNA was extracted. Goα mRNA leves were measured by competitive RT-PCR. Results As compared with group A, Goα mRNA leves in group B, D and E were low （P 〈 0.01 ）. Goα mRNA leves in group C were higher than that in group A, B, D and E （ P 〈 0.01 ）. No significant difference in Goα mRNA leves was noticed among group B, D and E （P 〉 0.05）. Conclusion T3 has dual effects on the expression of Goα gene in cultured rat cerebral cortex neurons. T3 down-regulated Goα mRNA in cultured neuron. However, in the absence of T3 , Goα mRNA was also very low. Thyroid hormone may exert their action on brain development by regulating the the expression of Goα gene.
出处
《中华内分泌代谢杂志》
CAS
CSCD
北大核心
2006年第4期392-395,共4页
Chinese Journal of Endocrinology and Metabolism
基金
国家自然科学基金(30200127)
