尿路上皮屏障相关蛋白在前列腺导管内的表达及意义

Expression and meaning of urothelial barrier related proteins in prostatic duct

目的:探索老年雄性SD大鼠前列腺导管内尿路上皮屏障的表达情况。方法:随机选取10只SD大鼠,予水合氯醛麻醉后取膀胱、前列腺部尿道及前列腺组织行病理连续切片,完成苏木精-伊红(HE)染色和免疫组织化学染色,检测各组织尿斑蛋白Ⅲ(UPⅢ)、闭锁小带蛋白-1(ZO-1)及闭锁蛋白(Occludin)的表达。另取20只SD大鼠同法取膀胱、前列腺腹侧叶和侧叶组织,随机均分两组,分别采用蛋白质免疫印迹(Western blot)和实时定量荧光酶联聚合反应(RT-PCR)检测各组织中UPⅢ、ZO-1和Occludin的表达。结果:HE染色结果显示膀胱和尿道内见极性排列尿路上皮细胞;前列腺导管尿道开口处见未呈极性排列的尿路上皮细胞,随着前列腺导管向腺泡腔底部延伸,前列腺导管开口处的尿路上皮细胞数量逐渐减少,最终转化为单层极性排列的腺上皮细胞。免疫组织化学染色示UPⅢ、ZO-1和Occludin在膀胱、尿道和前列腺导管开口处均呈阳性表达,其中UPⅢ在前列腺导管开口处的阳性表达随着导管向腺泡腔底部延伸而逐渐转为阴性,而ZO-1和Occludin在前列腺导管中均呈阳性。Western blot结果示膀胱、前列腺腹侧叶和侧叶3个部位UPⅢ的蛋白表达量分别为2 273.20±95.91、1 656.40±81.30和28.00±8.86;ZO-1蛋白表达量分别为1 811.20±87.10、845.20±110.14和30.00±16.17,Occludin蛋白表达量分别为1 911.20±71.56、916.80±104.22和32.80±6.72。RT-PCR检测结果示3种相关蛋白均在膀胱内表达,其中UPⅢ和Occludin也在前列腺中表达,腹侧叶表达高于侧叶,ZO-1在前列腺中表达极低。结论:老年雄性SD大鼠前列腺导管内存在一定量的尿路上皮屏障,这将为研究前列腺切除术后创面屏障的修复机制奠定基础。

Objective:To explore the expression of urothelial barrier in prostatic duct of aged male SD rats.Method:Ten SD rats were anesthetized with chloral hydrate and their bladders were collected,and serial pathological sections were done in prostatic urethra and prostate tissues.Then HE staining and immunohistochemical staining were done.The expression of UroplakinⅢ(UPⅢ),Zonula occludens-1(ZO-1)and occludin in prostatic duct were detected.Ventral lobe of prostate and lateral lobe of prostate samples of another 20 SD rats were obtained by the same method,and these rats were divided into two groups at random.Respectively,western blot and real-time fluorescence quantitative polymerase chain reaction(RT-PCR)were used to detect the expression of UPⅢ,ZO-1 and occludin in these tissues.Result:HE showed that urothelial cells were arranged with polarity in the bladder and urethra,and urothelial cells were observed at the orifice of prostatic duct in urethra,but not with polarity.The number of the urothelial cells gradually reduced with prostatic ducts extension to the bottom of the acinar lumen,and arranged by polarity into nonpolarity,until urothelial cells were turned into single polar arrangement of glandular epithelial cells.Immunohistochemical staining showed UPⅢ,ZO-1 and occludin were all positive in bladder,urethra and the urethral orifice of the prostatic duct.UPⅢdecreased gradually to negative expression with the duct extension to the bottom of the acinar lumen.While ZO-1 and occludin were positive throughout the prostate duct.Western blot results showed that the expression of UPⅢin bladder,ventral lobe of prostate and lateral lobe of prostate were 2 273.20±95.91,1 656.40±81.30 and 28.00±8.86.The expression of ZO-1 in these tissues were 1 811.20±87.10,845.20±110.14 and 30.00±16.17.The expression of occludin in these tissues were 1 911.20±71.56,916.80±104.22 and 32.80±6.72.RT-PCR showed that these three related proteins expressed in bladder,UPⅢand occludin also expressed in the prostate which the expression of ventral lobe was higher than that of lateral lobe.The expression of ZO-1 was extremely low.Conclusion:Urothelial barrier existed in prostatic ducts of aged male SD rats.The results will lay the foundation for the study of wound repair mechanism after prostatectomy.