过氧化物酶体增生物激活受体γ在大鼠出生前后心肌组织的表达规律

Expression Regularity of Peroxisome Proliferators-Activated Receptor γ in Cardiac Tissue of Rat before and after Birth

目的探讨过氧化物酶体增生物激活受体γ(PPARγ)在大鼠出生前后心肌组织发育中的表达规律。方法利用反转录-PCR和免疫蛋白印迹技术,检测18～20 d胎鼠组(胎儿期)、出生5～6 d(相当于人新生儿期)、出生10～12 d(相当于人幼儿期)和出生18～20 d新生大鼠(相当于人7～13岁)(每组各6只)心肌组织PPARγ mRNA及其蛋白的表达,并利用图像分析系统对其表达结果进行定量分析。结果胚胎18～20 d胎鼠心肌组织中PPARγ mRNA呈强阳性表达,出生后各组逐渐减弱;从胚胎18 d至出生18～20 d大鼠心肌组织中PPARγ蛋白的表达强度逐渐减弱,最终呈稳定表达。结论 PPARγ在大鼠心肌组织中的表达规律是从胎心开始,随着心脏的发育,心肌细胞中的PPARγ表达逐渐减少,提示PPARγ对心肌细胞的分化具有重要的调节作用。

Objective To investigate the expression regularity of peroxisome proliferators - activated receptor γ （PPARγ） in cardiac tissue of rat before and after birth. Methods Thirty Sprague Dawley rats were divided into embryo days 18 - 20 （ fetal）, postnatal days 5 - 6 （neonatal）, day 10 - 12 （childhood） and day 18 -20 （puberty） after birth ,6 cases of rats in each group. The PPARγ expressions regularity were detected by reverse transcription chain reaction and Western blot, and their quantitations were analyzed with image analysis system in cardiac tissue of rats in different stage before and after birth. Results The expression of PPARγ mRNA was strongly positive in the embryo myocardial cytoplasm at embryo day 18 -20 group, and decreased gradually in each group after birth. The expression of PPARγ protein decreased gradually and expressed stably in the rat myocardial cytoplasm from embryo days 18 to day 18 -20 after birth. Conclusions The expression regularity of PPARγ protein in myocardium begin with embryocardia,with the development of the heart, PPARγ expression decreases gradually and expresses stably,which hinted PPARγ plays a significant role in regulating cell desintegration and differentiation.