组织工程材料替代尿道缺损的实验研究

The experimental study of tissue engineering material replaced urethral defect

目的寻找理想的尿道修复材料。方法取5只兔尿道经脱细胞处理后制成尿道细胞外基质（ECM）。将15只目本大耳白兔随机分为实验组和对照组，试验组用尿道ECM替代正常尿道，对照组组间相互移植尿道。术后分期分批处死兔子，解剖观察泌尿系变化，取出移植物进行病理检查了解尿道再生情况。结果对照组兔子术后1、2周、4周均有膀胱尿潴留，移植物坏死，尿道狭窄。实验组动物于1周、2周、4周、8周、12周均未发生尿潴留，新生尿道通畅。病理检查对照组移植物全部坏死，实验组移植物进行性生长，尿道粘膜逐渐恢复连续。结论尿道ECM移植是治疗长段尿道狭窄、缺损的一种理想方法。

Objective To search for an ideal material for replacement of urethral defect .Method Extracellular matrix（ECM） was obtained from the urethrals of 5 rabbits by decellularization process. 15 rabbits were divided randomly into experimental group and control group. In experimental group of 9 rabbits, the resected urethra of 1.0 cm was repaired by the urethral ECM. In control group of 6 rabbits ,the resected urethra of 1.0 cm was replaced by allograff transplantation of untreated urethra. After operation all rabbits were executed and anatomized in different time, changes in the urinary system of the rabbits were observed then the grafts were resected for evaluation histologically and the immunohistochemically in order to observe the rejection reaction. Result All rabbits in control group were found urine retention and grafts were putrescent and urethras were stricture. But urine retention and urethral stricture were not found in experimental group rabbits after weeks of 1, 2,4,8,12 postoperation. All grafts in control group were necrostic under light microscopy. In experimental group, grafts grew progressively and muensa became consecutive gradually, irnmunohistochemical staining showed all cases were negative. Whereas they were positive in control group. Conclusions Urethral ECM transplantation is a perfect method for treatment of long urethral stricture or urethral defect.