Lazzeri Massimo, Vannucchi Maria Giuliana, Zardo Claudio, Spinelli Michele, Beneforti Patrizia, Turini Damiano, Faussone-Pellegrini Maria-Simonetta
Department of Urology, University of Ferrara, Via Savonarola 4, Ferrara, Italy.
Eur Urol. 2004 Dec;46(6):792-8. doi: 10.1016/j.eururo.2004.08.007.
Experimental and clinical evidences have shown the importance of the vanilloid receptor 1 (TRPV1) in the lower urinary tract. In humans, this receptor has been detected in nerve endings of primary sensory neurons, smooth muscle and connective tissue cells and in the rat also in the urothelium. The aim of this study is to identify, by immunohistochemistry, the cell types expressing TRPV1 in the human urinary bladder.
Specimens, obtained from normal urinary bladder by multiple biopsy and from ureter at the time of radical nefrectomy for renal cell carcinoma, were fixed and frozen. Full-thickness sections were processed for light and fluorescence microscopes. To label the TRPV1, three polyclonal antibodies were used: the anti-capsaicin receptor, the anti-VR1 (N-15) and the anti-VR1 (C-15).
Urothelium, smooth muscle cells, mast cells and endothelium were labelled and the labelling was intracytoplasmatic. In the urothelial cells, the labelling was slightly granular. In the bladder urothelium, the superficial cells were more intensely stained than the basal and club-shaped cells. VR1-positive nerve fibers were seen running single and/or in groups in the sub-urothelium and as single varicose fibers in the muscle coat, and VR1-positive nerve endings in the urothelium.
The present findings provide the evidence of the presence of TRPV1 on normal human urothelium where it could have important implications in the mechanism of action of intravesical vanilloids (capsaicin and resiniferatoxin).
实验和临床证据表明香草酸受体1（TRPV1）在下尿路中具有重要作用。在人类中，已在初级感觉神经元的神经末梢、平滑肌和结缔组织细胞中检测到该受体，在大鼠中还在尿路上皮中检测到。本研究的目的是通过免疫组织化学鉴定人膀胱中表达TRPV1的细胞类型。
通过多次活检从正常膀胱获取的标本以及在肾细胞癌根治性肾切除术时从输尿管获取的标本，进行固定和冷冻。对全层切片进行光镜和荧光显微镜处理。为标记TRPV1，使用了三种多克隆抗体：抗辣椒素受体、抗VR1（N - 15）和抗VR1（C - 15）。
尿路上皮、平滑肌细胞、肥大细胞和内皮细胞被标记，且标记位于细胞质内。在尿路上皮细胞中，标记呈轻微颗粒状。在膀胱尿路上皮中，表层细胞的染色比基底细胞和杵状细胞更强烈。可见VR1阳性神经纤维在尿路上皮下层单个和/或成组分布，在肌层中为单个曲张纤维，在尿路上皮中有VR1阳性神经末梢。
本研究结果提供了正常人类尿路上皮存在TRPV1的证据，这可能对膀胱内香草酸类物质（辣椒素和树脂毒素）的作用机制具有重要意义。
