胰岛素对3T3-L1脂肪细胞中极低密度脂蛋白受体基因表达的影响

体外培养3T3-L1细胞分化模型，研究不同浓度胰岛素及慢性胰岛素刺激对3T3-L1脂肪细胞中极低密度脂蛋白受体（VLDLR）基因表达的影响.在不同浓度胰岛素及胰岛素慢性刺激的干预下，用半定量RT-PCR检测细胞VLDLR mRNA水平的变化.微量化GOD-PAP法检测培养基中残存的葡萄糖.在细胞诱导分化过程中，胰岛素浓度的增高促进VLDLR的表达；胰岛素慢性刺激下，VLDLR表达因浓度差异呈现不同变化.研究结果表明，胰岛素的浓度及慢性刺激对3T3-L1脂肪细胞的成熟和VLDLR基因的表达有显著作用，而胰岛素抵抗明显减低成熟脂肪细胞VLDLR的表达.

Effect of Insulin on VLDLR Gene Expression in 3T3-L1 Adipocyte

The effect of different insulin concentration and chronic insulin stimulation on the very low density lipoprotein receptor(VLDLR)gene expression were researched in the differentiations of 3T3-L1 preadipocytes and in mature adipocytes.3T3-L1 cells were induced to differentiate by using IBMX,dexamethasone and different concentration of insulin.Fully differentiated adipocytes were chronically stimulated by various concentration of insulin.And the relatively quantitative RT-PCR was used to detect the expression of VLDLR during 3T3-LI cells differentiation and mature adipocytes.The microscale way of GOD-PAP was used to detect glucose remained in medium.Compared with control,the increasing insulin concentration boosted the gene expression of VLDLR(P<0.05).VLDLR gene expression was dramatically changed under chronic insulin stimulation in adipocytes,it depended on the concentration of insulin.Insulin plays an important role in induction of 3T3-L1 cells,and it has great effect on VLDLR gene expression.Insulin resistance caused by chronic high insulin stimulation can down-regulated VLDLR gene expression in mature adipocytes(P<0.001).These provide evidence to further establish a mechanism through which insulin regulate the VLDLR gene expression in adipocytes.