[The pathological characters of urothelial barrier in prostatic ducts of elderly SD rats]

Objective: To investigate the pathological characters of urothelial barrier in prostatic ducts of elderly male SD rats. Methods: Ten elderly male SD rats were anesthetized with chloral hydrate and then took the bladder, prostatic urethra and prostate tissues for serial pathological sections and HE staining. Immunohistochemical method was used to detect the expression of the Cytokeratin 7 (CK7), Cytokeratin 20 (CK20), Uroplakin Ⅲ (UP Ⅲ), Zonula occludens-1 (ZO-1) and Occludin in issues, and to make densitometric analysis (IA) on immunohistochemical results of each antibody. Results: HE staining observed that urothelial umbrella cells exist in the bladder, prostatic urethra and proximal prostatic duct. Immunohistochemical method showed the CK7, UPⅢ, ZO-1 and Occludin were positive in bladder, prostatic urethra and prostatic duct, while CK20 was negative. CK7 and UPⅢ were positive in the proximal prostatic duct, and negative in the bottom of the ductal acinar lumen; ZO-1 and Occludin were positive in prostatic duct. The IOD/Area values of CK7 and UP Ⅲ, in bladder, prostatic urethra, proximal prostatic duct, the middle of prostatic duct and bottom of the ductal acinar lumen, were 0.16, 0.13, 0.06, 0.05, 0.00 and 0.17, 0.16, 0.08, 0.05, 0.00(P<0.05,respectively). The expression of ZO-1 and Occludin in bladder (0.14 and 0.13) were higher than those in other tissues (0.11-0.12 and 0.09-0.10, P<0.05); the expression of ZO-1 and Occludin, which in proximal prostatic duct to the middle of prostatic duct and bottom of the ductal acinar lumen, had no significant difference (0.12-0.11 and 0.09-0.09, P>0.05). The IA values of CK20 were extremely low (0.00-0.01, P>0.05). Conclusion: Urothelial barriers partially exist in the prostatic ducts of elderly male SD rats, and with the prostatic ducts gradually extending to the bottom of acinar lumen, the urothelial barriers disappear. The results lay a foundation for further study on the repair of urinary epithelial barrier after prostatectomy.