血小板源性生长因子受体α阳性细胞在先天性肾盂输尿管连接部梗阻发病中的表达及意义

目的探讨血小板源性生长因子受体α(platelet-derived growth factor receptor alpha-positive,PDGFRα)阳性细胞在儿童先天性肾盂输尿管连接部梗阻(ureteropelvic junction obstruction,UPJO)发病中的表达与意义。方法应用免疫组织荧光双染方法对首都医科大学附属北京儿童医院30例UPJO患儿肾盂输尿管连接部(ureteropelvic junction,UPJ)组织(为UPJO组)及10例因肾脏肿瘤行肾输尿管切除术患儿的UPJ组织(排除肾盂输尿管连接部狭窄以及其他泌尿系统畸形,病理结果证实肿瘤未侵犯肾盂输尿管交界处,为对照组)进行染色观察,同时分析所有患儿PDGFRα阳性细胞表达的小电导钙离子激活钾离子通道3型(small conductance calcium-activated potassium channel 3,SK3)表达水平。结果PDGFRα阳性细胞表型区别于Cajal间质细胞,与平滑肌细胞、神经纤维关系密切。PDGFRα细胞在UPJO组中的分布与对照组相似,而该细胞表达的SK3通道在UPJO组中显著低于对照组。结论UPJO患儿肾盂输尿管连接部PDGFRα细胞上SK3通道表达降低,推测SK3通道可能通过干扰UPJ蠕动参与UPJO发病过程。

Expression and significance of platelet-derived growth factor receptor alpha-positive cells in stenotic tissue of congenital ureteropelvic junction obstruction

Objective To observe the expression of platelet-derived growth factor receptorα-positive(PDGFRα+)cells in congenital ureteropelvic junction obstruction(UPJO)for exploring their role in the pathogenesis of congenital hydronephrosis in children.Methods UPJO group was composed of specimens of ureteropelvic junction(UPJ)harvested during pyeloplasty(n=30)while control group involved the specimens of normal ureter(nephrectomy for tumor;n=10).The immunofluorescence of specimens was examined by light microscopy and computerized image analysis for the expression and distribution of PDGFRα+cells in each group.In addition,small conductance calcium-activated potassium channel 3(SK3)and closely associated cells consisting of smooth muscle cells(SMCs),interstitial cells of Cajal(ICCs)and nerve fibers were examined.Results Located in close proximity to SMCs,ICCs and nerve fibers,PDGFRα+cells expressed SK3 channels capable of mediating purinergic inhibitory neurotransmission in SMCs.The expression of SK3 channels decreased obviously in UPJ obstruction in PDGFRα+cells as compared with controls.Conclusion There is a down-regulation of SK3 channels in UPJO in PDGFRα+cells.And SK3 channels may be involved in the pathogenesis of UPJO by perturbing normal peristalsis of human UPJ.