He Fan, Yang Zhenxing, Dong Xingyou, Fang Zhenqiang, Liu Qian, Hu Xiaoyan, Yi Shanhong, Li Longkun
Department of Urology, Xinqiao Hospital, the Third Military Medical University, No. 183 Xinqiao Main Street, Shapinba Dist., Chongqing, 400037, People's Republic of China.
Int Urol Nephrol. 2018 Apr;50(4):639-645. doi: 10.1007/s11255-018-1816-y. Epub 2018 Feb 19.
To explore the role of HCN channels in ureteral peristaltic dysfunction by comparing the changes in HCN channel levels between normal and tuberculous ureters.
A total of 32 specimens of human upper ureters were collected by nephrectomy from patients with renal tumor (control group, n = 16) or from patients with renal tuberculosis (experimental group, n = 16); the two groups did not receive radiotherapy, chemotherapy, immunotherapy, or any other special treatment before the surgical procedure. An experimental study on smooth muscle strips of human upper ureters showed variation in contraction amplitude and frequency after adding ZD7288, a specific blocker of HCN channels. The expression of HCN channels in the ureter was confirmed by Western blot (WB) and by confocal analysis of double immunostaining for c-kit and HCN channel proteins.
Before the addition of ZD7288, the experimental and control groups showed significant differences in the frequency and amplitude of the spontaneous contraction of isolated ureteral smooth muscle strips. After ZD7288 was added, the frequency and amplitude of the contractions of the ureteral smooth muscle strips were significantly lower in both groups. The differences observed before and after ZD7288 treatment in each group were significant (P < 0.001), and the difference in contraction amplitude observed between the two groups before ZD7288 was also significantly different (P < 0.001). By using WB technology, we showed that the expression of HCN channels was present in normal human ureters, with the expression of HCN4 and HCN1 being the highest; the expression of HCN4 and HCN1 in the control and experimental groups were both statistically significant (P < 0.001). HCN4 and HCN1 were expressed in the mucosal and smooth muscle layers of human control ureters and tuberculous ureters, as revealed by a confocal analysis of double immunostaining for c-kit and HCNs proteins; there were significant differences between the two groups (P < 0.001).
Four HCN channels are expressed in the ureter, mainly HCN4 and HCN1, suggesting that HCN channels are involved in the peristaltic contraction of ureteral ICCs, which may be an important reason for peristaltic dysfunction in ureteric tuberculosis.
通过比较正常输尿管和结核性输尿管中HCN通道水平的变化，探讨HCN通道在输尿管蠕动功能障碍中的作用。
通过肾切除术收集32例人上段输尿管标本，其中肾肿瘤患者（对照组，n = 16）或肾结核患者（实验组，n = 16）；两组在手术前均未接受放疗、化疗、免疫治疗或任何其他特殊治疗。对人上段输尿管平滑肌条的实验研究表明，添加HCN通道特异性阻滞剂ZD7288后，收缩幅度和频率发生变化。通过蛋白质免疫印迹法（WB）以及对c-kit和HCN通道蛋白进行双重免疫染色的共聚焦分析，证实输尿管中HCN通道的表达。
在添加ZD7288之前，实验组和对照组在离体输尿管平滑肌条自发收缩的频率和幅度上存在显著差异。添加ZD7288后，两组输尿管平滑肌条的收缩频率和幅度均显著降低。每组在ZD7288治疗前后观察到的差异均具有统计学意义（P < 0.001），并且在ZD7288之前两组之间观察到的收缩幅度差异也具有显著统计学意义（P < 0.001）。通过WB技术，我们发现HCN通道在正常人输尿管中表达，其中HCN4和HCN1的表达最高；对照组和实验组中HCN4和HCN1的表达均具有统计学意义（P < 0.001）。对c-kit和HCN蛋白进行双重免疫染色的共聚焦分析显示，HCN4和HCN1在人对照输尿管和结核性输尿管的黏膜层和平滑肌层中表达；两组之间存在显著差异（P < 0.001）。
输尿管中表达四种HCN通道，主要是HCN4和HCN1，提示HCN通道参与输尿管ICC的蠕动收缩，这可能是输尿管结核蠕动功能障碍的重要原因。
