He Qian, Yu Yan-Lan, Li Gong-Hui, Chen Sheng
Department of Urology, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, China (mainland).
Med Sci Monit. 2017 May 21;23:2400-2407. doi: 10.12659/msm.904406.
BACKGROUND The aim of this study was to confirm that the interstitial cells of Cajal (ICCs) in the dome wall of the bladder are pacemaker cells, and that the dome wall of the bladder acts as a pacemaker site in the detrusor instability (DI) rat model. MATERIAL AND METHODS The model of DI in Wistar rats was established and urodynamic studies measuring the bladder volume and pressure were performed. The detrusor excitability was investigated using the amplitude and frequency of phasic contraction of strips. The localization and quantity of ICCs was identified by immunohistochemistry and c-KIT protein expression in the rat bladder. PCR assay and Western blot were used to assess the expression of HCN2 and Cx43. RESULTS The bladder capacity, residual volume, voiding volume, and maximum voiding pressure were significantly increased in the DI group. The contraction frequency and amplitude of the strips from the dome of the bladder in the DI group were higher than the triangle, body, and base parts. Both the concentration of c-KIT positive ICCs cells and expression of the c-KIT protein in the dome wall were higher than in other parts of the bladder. The expression of HCN2 and Cx43 in each part of the DI rat group were obviously higher than each part in the control group. Compared to the body, base, and triangle parts, the expression of HCN2 and Cx43 in the dome wall were obviously higher in the DI group. CONCLUSIONS The quantity of ICCs was higher in the dome wall and the dome wall of bladder acts as a pacemaker site in the DI rat model.
背景 本研究的目的是证实膀胱穹窿壁中的 Cajal 间质细胞（ICCs）是起搏细胞，并且膀胱穹窿壁在逼尿肌不稳定（DI）大鼠模型中作为起搏部位。
材料与方法 建立 Wistar 大鼠 DI 模型，并进行测量膀胱容量和压力的尿动力学研究。使用条带的相性收缩幅度和频率研究逼尿肌兴奋性。通过免疫组织化学和大鼠膀胱中 c-KIT 蛋白表达来鉴定 ICCs 的定位和数量。采用 PCR 检测和 Western 印迹法评估 HCN2 和 Cx43 的表达。
结果 DI 组的膀胱容量、残余尿量、排尿量和最大排尿压力显著增加。DI 组膀胱穹窿部条带的收缩频率和幅度高于三角区、体部和底部。膀胱穹窿壁中 c-KIT 阳性 ICCs 细胞浓度和 c-KIT 蛋白表达均高于膀胱其他部位。DI 大鼠组各部位 HCN2 和 Cx43 的表达明显高于对照组各部位。与体部、底部和三角区相比，DI 组膀胱穹窿壁中 HCN2 和 Cx43 的表达明显更高。
结论 在 DI 大鼠模型中，膀胱穹窿壁中 ICCs 的数量较多，且膀胱穹窿壁作为起搏部位。
