EGF和bFGF在大鼠不同发育阶段肠道定位和表达特征的比较研究

The expression characteristics and their biological significance of epidermal growth factor and basic fibroblast growth factor in intestine from the different developmental rats

目的 :研究表皮细胞生长因子 (EGF)和碱性成纤维细胞生长因子 (b FGF)在胚胎、新生以及成年 3个不同发育阶段 ,大鼠肠道的表达特征及其可能的生物学意义。方法 :取胚胎、新生和成年大鼠小肠 ,经 4%多聚甲醛固定、包埋与切片后 ,用链酶卵白素免疫组织化学法研究 EGF和 b FGF两种生长因子的定位与表达特征。结果 :EGF的阳性表达可见于胚胎、新生以及成年 3个不同发育阶段大鼠小肠 ,主要位于小肠黏膜上皮细胞、固有层细胞和黏膜肌层细胞胞浆 ,其表达强度为强阳性。 b FGF在胚胎、新生与成年大鼠小肠表达的定位与EGF类似 ,但在整个发育过程中表达为弱阳性或阳性。结论 :EGF在不同发育阶段大鼠小肠呈强阳性表达 ,表明了它对肠道的发生、表型维持以及损伤后的修复十分重要。与 EGF相比 ,大鼠胚胎期、新生以及成年期b FGF低表达特征 ,表明 b FGF参与了动物不同发育阶段肠道的发育过程 ,但其作用可能较

Objective:To explore the localization and expression characteristics of the epidermal growth factor (EGF) and basic fibroblast growth factor (bFGF) in intestine from the different developmental rats.Methods:Biopsies from embryonic rats(17 days, n =5),newborn rats(2 days, n =5) and adult rats(four weeks, n =5 ) were taken,embedded and cut.Immunohistochemical method was used to observe the localization and expression amount of both growth factors.Results:Positive immunohistochemical signal of EGF could be found in intestines from embryonic,newborn and adult rats,mainly in the intestinal villus cells,endothelial cells and fibroblasts.With the increase in age,the expression amount of EGF was increased.Although the positive signal of bFGF could also be found in the intestines from embryonic,newborn and adult rats,however,the signal of bFGF in intestine was weaker compared with that of EGF.Conclusions:The results indicate that the endogenous EGF and bFGF are involved in the action of the intestinal development in embryonic stage and the wound healing in adult after injury.However,the difference in expression amount of both growth factors indicate that the EGF may play a key role in intestinal development and repair compared with bFGF.