摘要
目的探讨胰岛素受体底物(IRS-1I、RS-2)基因在宫内发育迟缓(IUGR)新生鼠心肌、骨骼肌(股四头肌)中的表达及意义。方法采用母孕期饥饿法建立IUGR新生鼠模型,正常新生鼠作对照,应用RT-PCR技术检测心肌、股四头肌组织IRS-1I、RS-2mRNA水平,凝胶电泳条带用成像系统照相定量分析结果,分别计算PCR产物条带与-βactin条带光密度值的比值,作为目的基因相对表达量。结果IUGR鼠出生时体质量、身长显著小于对照组(P均<0.01)。IUGR新生鼠心肌IRS-1 mRNA相对表达水平显著高于对照组(t=2.568 P=0.022),股四头肌IRS-1 mRNA相对表达水平、心肌IRS-2 mRNA相对表达水平显著低于对照组(t=2.868 P=0.012;t=2.358 P=0.035),股四头肌IRS-2 mRNA相对表达水平与对照组相比无显著差异(t=1.426 P=0.177)。结论IUGR对心肌、骨骼肌IRS-1基因表达的影响具有组织选择性,心肌IRS-1基因表达上调是适应宫内营养不良环境的结果;骨骼肌IRS-1基因表达下降,并可能“程序化”,可能是IUGR易患代谢综合征的分子机制之一。
Objective To investigate the expressions and significanees of insulin receptor substrate - 1 （ IRS - 1 ） and IRS - 2 in muscle of newborn rats with intrauterine growth retardation（IUGR）. Methods IUGR animal models were established by maternal nutrition restriction. The levels of IRS - 1 mRNA and IRS - 2 mRNA in cardiac muscle and quadriceps femoris were detected by RT - PCR. Electrophoresis gels with specific positive bands were quantified by complete gel documentation and analysis system. The ratio of IRS/β - actin waa calculated. Results Body weight and body length of newborn IUGR group were significantly lower than those in control group（all P 〈 0.01 ）. The relative expression level of IRS 1 mRNA in cardiac muscle of IUGR group was significantly higher than that in control group（ t = 2. 568 P = 0. 022）. The relative expression levels of IRS 1 mRNA in quadriceps femoris and IRS - 2 mRNA in cardiac muscle of lUGR group were significantly lower than those in control group（ t = 2. 868 P 0.012;t=2.358 P=0.035）, respectively. The relative expression level of IRS-2 mRNA in quadriceps femoris hadno significant difference with that in control group（ t= 1. 426 P = 0.177）. Conclusions Tissue- specific gene expression of IRS- 1 is found in IUGR children, Up - regulation of IRS- 1 gene expression in cardiac muscle of IUGR group is the result of adaptation to maternal undemutrition while programming of down - regulation in skeletal muscle may be one of the molecular mechanisms of IUGR having increased risks of metabolic syudrome.
出处
《实用儿科临床杂志》
CAS
CSCD
北大核心
2006年第8期460-462,共3页
Journal of Applied Clinical Pediatrics
基金
国家杰出青年科学基金项目资助(30125019)
国家重点基础研究发展计划项目资助(2005CB522507)
关键词
胰岛素受体底物
胎儿
生长迟缓
代谢综合征
基因表达
insulin receptor substrate
fetal
growth retardation
metabolic syndrome
gene expression
