内镜直视下尿道黏膜电凝法制作兔尿道狭窄模型

Establishment of urethral stricture in rabbit model with visual endoscopic urethroelectrocoagulation

目的:探讨小儿膀胱电切镜直视下尿道黏膜电凝法制作兔尿道狭窄模型的可行性和有效性.方法:随机选取15只成年雄性新西兰大白兔,麻醉后F13号小儿膀胱电切镜在球部尿道电凝一周,电凝长度10 mm,深达尿道黏膜下层.另选取6只成年雄性新西兰大白兔,同法麻醉后行尿道镜检,不做尿道黏膜电凝(对照组).30 d后逆行尿道造影和尿道镜检观察电凝损伤处尿道狭窄形成情况,HE染色和天狼星红染色观察狭窄段尿道病理形态改变.结果:实验组死亡2只,对照组无死亡.实验组存活13只动物均发生尿道狭窄[管腔缩窄(78.45±7.95)%],造模成功率100%.实验组球部尿道直径较对照组显著减低[(4.08±0.84)mmvs(8.33±1.63)mm].尿道镜检见实验组所有动物球部尿道均发生狭窄,对照组无狭窄发生.实验组狭窄段尿道黏膜下纤维组织增生达肌层伴较多成纤维细胞浸润,胶原染色呈猩红色;对照组无纤维组织增生,胶原染色呈淡红色.结论:内镜直视下尿道黏膜电凝法制作兔尿道狭窄模型,操作简单,造模成功率高,可引起典型的尿道狭窄病理改变,是一种理想的尿道狭窄动物模型制作方法.

AIM： To explore the efficiency and feasibility of establishing an experimental model of urethral stricture with visual endoscopic eleetrocoagulation in rabbits. METHODS： Fifteen randomly selected adult male New Zealand rabbits underwent videourethroscopy with a pediatric resectoscope （F13）, and a 10 mm-long circumferential electrocoagulation of the bulbar urethra was performed to the ulceration of the mueosa. Six animals underwent the same procedures without the application of electrocoagulation （ control group）. Thirty days after coagulation, the urethral stricture formation was detected by retrograde urethrogram, videourethroscopy, HE and Sirius Red staining. RESULTS： Two rabbits in the study group died and none in the control. The survived rabbits in the study group all developed significant urethral stricture, with the urethral lumen decreasing by （78.45 ± 7.95） %. No stricture was observed in the control group. Histological examination showed a normal urethra in each control case, while in the study group a thick fibrosis was seen in stricture site with abundant typical fibroblasts and high expression of collagen demonstrated by Sirius Red staining. CONCLUSION： Visual endoscopic electrocoagulation is a feasible way to establish urethral stricture models, which induces a high stricture rate and typical pathologic changes.