【摘要】 目的探讨NKx2.5基因mRNA及其蛋白在肥胖孕鼠胚胎畸形心脏中的表达水平及相关意义。方法 3周龄SPF级SD雌鼠100只,随机分为两组:正常组(40只)给予基础饲料;高脂组(60只)给予高脂饲料。8周后,以高脂组体重超过正常组平均体重的20%且血清总胆固醇(TC)、甘油三酯(TG)含量显著高于正常组的作为肥胖雌鼠,随机抽取20只肥胖雌鼠和正常雌鼠分别与雄鼠交配获取肥胖组孕鼠和对照组孕鼠。取孕13、15、17、19 d胚胎鼠心脏,通过切片进行组织学观察以确定心脏畸形情况,采用RT-PCR法检测NKx2.5基因的mRNA表达,采用Western blot方法检测NKx2.5蛋白表达。结果肥胖组孕鼠胚胎心脏畸形率显著高于对照组孕鼠(P<0.01);肥胖组孕鼠各孕龄胚胎畸形心脏NKx2.5基因mRNA及其蛋白表达比对照组孕鼠正常胚胎显著降低(P<0.05)。结论孕鼠肥胖导致胚胎心脏畸形率升高;孕鼠肥胖抑制胚胎心脏NKx2.5基因和蛋白表达,可能导致心脏发生发育缺陷从而造成先天性心脏畸形。更多还原

【Abstract】 Objective To explore the expression and significance of NKx2.5 gene mRNA and its protein in the embryos heart defects induced by pregnant rat obesity.Methods 100 three-week old SD female rats were randomly divided into control group(n=40) and high-fat group(n=60).The rats in the control group were fed with standard forage and the rats in the high fat group were fed with high-fat diet.After 8 weeks,the rats in the high-fat group with body weight more than 20% of average body weight of control group and total cholesterol,triglyceride level were significantly higher than control group were selected as the obese rats.Random choice of obese rats(n=20) and normal rats(n=20) mate with male counterparts to access to pregnancy.All the embryos were removed on the thirteenth,fifteenth,seventeenth and nineteenth day and cut section for microscopic examination to observe heart malformation.The expression of NKx2.5 mRNA by RT-PCR was observed.The expression of NKx2.5 protein by Western blot was investigated.Results The number of rats with the embryonic heart defects in obese pregnant rat group were significantly higher than those in the control group(P<0.01).The expression of NKx2.5 mRNA and protein was significantly decreased in the embryonic heart defects rats of obese rats versus the normal heart rats of the control group(P<0.05).Conclusion Pregnant rat obesity can increase the incidence of embryonic heart defects.Pregnant rat obesity can restrain the expression of NKx2.5 mRNA and protein in the embryos heart,which might lead to the morphological changes of heart and congenital heart defects.更多还原