表皮生长因子及其受体分布在青、老年大鼠肾切除术后留存肾代偿早期的改变

The age-related differences of EGF/EGFR expression in the early process of compensatory renal growth following uninephrectomy

目的 观察表皮生长因子 (EGF)蛋白及其受体 (EGFR)表达的改变 ,比较青、老年大鼠留存肾代偿过程的差异。方法 雄性Wistar大鼠青年组 60只 ,老年组 32只。行左肾切除术 ,并分别于术后 1、3、7、14d随机处死青年组各 12只 ,老年组各 8只。取右肾为代偿肾。EGF及EGFR免疫组织化学染色采用链菌素亲生物素蛋白 过氧化酶连接法。用IBSA 2 0 0 0图像处理系统对EGFR含量进行半定量分析。结果 术后 14d青、老年组留存肾增重分别为 5 4.2 %和14 .2 %。肾代偿时EGF由原局限性分布变为弥漫性分布 ,其表达增加程度以青年组为明显 ;EGFR蛋白分布量在皮质均有增加 ,老年组增加较青年组迟缓。结论 EGF及EGFR在留存肾代偿早期起重要作用 ,肾代偿时 ,肾内EGF通过自分泌和旁分泌而发生作用。

s Objective To study the role of EGF/EGF R in the early stage of compensatory renal growth. Methods Immunohistochemical techniques were used to inves tigate the changes in EGFR and EGF protein expression in the early process of co mpensatory renal growth following uninephrectomy in young and old Wistar rats.Results A rapid growth period of remnant kidney appeare d in the young rats in 1～7 days following uninephrectomy, but not in old rats. EGF and EGFR protein expression was the same in normal kidneys, but has differen t changes in the compensatory kidneys of the young and old groups.Conclusion EGF and EGFR might play an important role in t he early stage of compensatory renal growth. Retard increase of EGF and EGFR proteins in the remnant kidney may be one of the reasons of the low compensatory state of the remnant kidney in the old rats. EGF origin in the remnant kidney functions through renal autocrine and paracrine.