胰岛素受体底物在宫内发育迟缓大鼠胰腺组织中的表达

Expression of insulin receptor substrates in pancreas of rats with intrauterine growth retardation

目的研究胰岛素受体底物1(IRS-1)和胰岛素受体底物2(IRS-2)在宫内发育迟缓(IUGR)大鼠生后0周、3周和8周胰腺组织中的表达,探讨IUGR个体易患代谢综合征的分子机制。方法采用母孕期低蛋白饮食法建立IUGR大鼠模型,应用RT-PCR技术检测子鼠在生后0周、3周、8周胰腺组织中IRS-1和IRS-2mRNA水平。采用Western杂交检测IRS-1和IRS-2蛋白的表达。母孕期得到正常饮食的子鼠作为对照组。结果 IUGR组0周、3周、8周胰腺组织IRS-2mRNA和蛋白表达水平均显著低于对照组(P<0.05),IRS-1mRNA和蛋白表达水平与对照组相比差异无统计学意义(P>0.05)。结论 IUGR子鼠生后0周、3周和8周胰腺组织中IRS-2mR-NA和蛋白水平显著下降,可能是IUGR个体易患代谢综合征的分子机制之一。

Objective To study the expression of insulin receptor substrate-1（IRS-1） and insulin receptor substrate-2（IRS-2） in pancreas of rats with intrauterine growth retardation（IUGR）.Methods An IUGR rat model was prepared by protein malnutrition during pregnancy.The pancreas samples of the IUGR pups were obtained at birth,and 3 weeks and 8 weeks of age.The expression of IRS-1 and IRS-2 mRNA were ascertained by RT-PCR.Western blot was used to measure the protein expression of IRS-1 and IRS-2.The rat pups born from the mother rats who received normal diet during pregnancy severed as the control group.Results The expression levels of IRS-2 mRNA and protein in pancreas of the IUGR group were significantly lower than those in the control group at all three time points（P0.05）.There were no significant differences in the expression levels of IRS-1 mRNA and protein in pancreas between the IUGR and the control groups.Conclusions The IRS-2 expression levels in pancreas in IUGR rats decrease significantly at birth,and 3 weeks and 8 weeks of age.This might be one of the molecular mechanisms for the development of metabolic syndrome in later life in IUGR individuals.