尿道下裂术后尿道瘢痕的对比实验研究

Comparative experimental study on urethral scar following hypospadiac repair

目的:对比尿道下裂不同术式的伤口愈合过程,为术后尿道瘢痕性狭窄的防治提供理论依据。方法:制作尿道下裂动物模型,采用3种术式修复尿道。系统动态观察伤口愈合、瘢痕增生情况,以及细胞因子α-平滑肌肌动蛋白(α-SMactin)和转化生长因子β1(TGF-β1)在伤口中的表达。结果:Mathieu组与Onlay island flap(Onlay)组尿道腹侧胶原增生显著,明显强于尿道板正中切开卷管(Tubularized incised plate urethroplasty,TIPU)组(P<0.05)。TIPU组与Mathieu组和Onlay组比较,术后6周、3月TGF-β1与α-SMactin表达均明显减弱(P<0.01)。结论:TIPU重建的尿道更接近正常解剖结构,尿道壁瘢痕增生较轻,是一种较为理想的手术方式。尿道愈合过程中成纤维细胞保持长时间活性,可能是尿道下裂术后尿道狭窄形成及渐进加重的病理基础。

Objective：To compare characters of urethral healing after different surgical procedures to provide theoretical support for preventing and curing urethral scaring stricture after hypospadias repair. Methods： Hypospadiac animal model was established and three surgical procedures were adopted to repair urethra. The dynamic changes of urethral healing and scar were observed, the expressions of α-SMactin and TGF-β 1 were examined. Results：Mathieu and Onlay island flap （Onlay） had notable collagenous proliferation, which was significantly stronger than that of Tubularized Incised Plate urethroplasty （TIPU） （P〈0.05）. The expressions of TGF-β 1 and α-SMactin were markedly higher in Mathieu and Onlay than that in TIPU at 6 weeks and 3 months. Conclusion：TIPU is a comparatively ideal surgical procedure since urethra repaired by TIPU is more similar to normal anatomy and urethral scar proliferation was less than that in Mathieu and Onlay urethroplasty. The activity of fibroblasts kept long in all these urethroplasties,which may be the pathological foundation for the formation and gradual aggravation of urethral stricture following hypospadiac repair.