先天性肾积水肾脏及其尿液中水通道蛋白2表达的相关性研究

目的 探讨先天性肾积水患儿肾脏水通道蛋白2(aquaporin-2,AQP2)表达水平及其尿液AQP2表达水平之间的相关性.方法 选取20例单侧先天性肾盂输尿管连接处梗阻肾积水肾脏,其中轻度和重度积水肾脏各10例,并选取8例正常肾脏作为对照组.应用免疫组织化学方法检测肾脏AQP2表达水平,并采用酶联免疫吸附法(ELISA)检测其尿液中AQP2浓度.结果 AQP2阳性着色位于肾脏集合管主细胞胞膜和胞质.积水肾脏AQP2表达水平下降和其尿液中AQP2表达水平下降及尿渗透压下降相一致.重度积水组显著低于轻度积水组,重度和轻度积水组均显著低于正常对照组(P＜0.05).积水肾脏AQP2表达水平与其尿液AQP2表达水平以及尿渗透压均有显著正相关性(分别为r尿AOY2=0.706,P＜0.05;r尿渗透压=0.810,P＜0.05).结论 随着先天性.肾积水患儿积水程度增加,其肾脏AQP2表达水平和其尿液AQP2浓度及尿渗透压均明显下降.检测尿液AQP2浓度可间接反映肾脏中AQP2的表达情况,为临床评估肾脏浓缩稀释功能损害程度提供依据.

Correlation between the expression of AQP2 in hydronephrotic kidney tissue and urine in children with congenital hydronephrosis

Objective To investigate the relationship between the expression of aquaporin-2(AQP2) in hydronephrotic kidney(HNK)and urine in children with congenital hydtonephrosis.Methods Twenty patients with congenital unilateral pyeloureteric junction obstruction(PUJO)were chosen for this study,in whom 10 suffered mild hydronephrosis and 10 suffered severe hydronephrosis,with the mean age of 61.2±30.7 months.Eight nortnal ehildren served as controls,with the mean age of 58.9±34.2 months.The expression of AQP2 in HNK tissue was determined by immunohistochemisty,and the AQP2 levelin urine was determined by enzyme-linked immunosorbent assay(ELISA).Results Positive immunoreactivity of AQP2 was found in the apical membrane and intracellular vesicles of the principal cells in collecting ducts.The decreasing of HNK tissue and urine AQP2 expression level was consistent with the decreasing of urinary osmotic pressure in patients with hydronephrosis.The AQP2 expression in severe hydronephrotic group was significantly lower than that in mild hydronephrotic group(P＜0.05),and AQP2 expression in abovementioned two groups was significantly 10wer than that in the controls(P＜0.05).A positive correlation between the expression level of AQP2 in HNK tissue and urinary AQP2 level,and urinary osmotic pressure were found(r=0.706,P＜0.05;r=0.810,P＜0.05).Conclusions With the malignancy of hydronephrosis,the expression of AQP2 in HNK tissue and the urinary AQP2 levels and the urinary osmotic pressure have parallel decreasing,indicating the change of urinary AQP2 level may be used as a marker to predict the change of the expression of AQP2 in congenital HNK tissue,thus it may provide evidence for evaluating the urinary concentrating capacity.