Podocalyxin在大鼠嘌呤霉素肾病模型中的表达及其意义

目的:研究大鼠嘌呤霉素肾病(PAN)模型中podocalyxin的表达,探讨其在蛋白尿发生中的意义.方法:建立PAN模型,应用光镜、电镜观察肾脏病理改变,免疫荧光法检测podocalyxin在肾脏的表达与分布.结果:①PAN 4 d组大鼠24 h尿蛋白量较对照组升高(P＜o.01),PAN 7 d组达高峰(P＜0.001),于28 d逐渐下降至正常.②透射电镜显示PAN 4 d组大鼠足突部分融合,PAN 7 d组大鼠足突广泛融合,PAN 28 d组大鼠足突形态有所恢复.③免疫荧光显示podocalyxin在肾小球表达,PAN 4 d组podocalyxin的表达较对照组降低(P＜0.05).PAN 7 d组表达明显低于对照组(P＜0.01).PAN 28 d组podocalyxin的表达明显高于PAN 7 d组(P＜0.01),与蛋白尿产生明显相关.结论:大鼠PAN模型中,podocalyxin的表达减少可引起足突融合,并与蛋白尿产生密切相关.

Expression of Podocalyxin in Rats with Puromycin Aminonucleoside Nephropathy

Objective: To investigate the expression and possible significance of podocalyxin in the development of proteinuria in rats with puromycin aminonucleoside nephropathy(PAN).Methods: PAN model was established by a single injection of puromycin aminonucleoside.The glomerular morphology and podocyte ultrastructure were observed under the light and transmission election microscopies respectively.The expression of podocalyxin was detected by using immunofluorescence method.Results: ①Proteinuria expression was increased 4 days after puromycin aminonucleoside injection and reached a peak on the 7th day(P<0.01);②In the process of the development of PAN,the foot process fusion was observed on the 4th day following puromycin aminonucleoside injection and wildly foot process fusion on the 7th day;③The expression of podocalyxin was significantly down-regulated with the progression of proteinuria,and recovered with the normalization of the urine protein excretion.Conclusion: A dramatic alteration of podocalyxin protein expression in PAN suggests its potential relationship with the foot process fusion and the development of proteinuria.