丝裂霉素预防大鼠胆管损伤后狭窄的体内研究

Prophylaxis of post-injury bile duct stenosis with mitomycin in vivo

目的探讨局部浸润丝裂霉素对胆管电凝后狭窄的预防作用。方法健康雄性SD大鼠38只,采用电凝法建立胆总管损伤模型,然后随机分为模型组(n=10)、实验1组(n=10)、实验2组(n=10)和药物空白对照组(n=8)。实验1组及2组分别在胆管损伤处用吸附0.4、0.6mg/ml丝裂霉素(体积均为1ml)的明胶海绵包绕并充分接触5min,药物空白对照组用浸润1ml注射用水的明胶海绵包绕。15d后取血检测肝功能,处死动物,取狭窄段及周围胆总管标本,光镜观察组织学改变,免疫组化检测转化生长因子β(TGF-β)和增殖细胞核抗原(PCNA)的表达。结果模型组术后15d胆管损伤处管腔狭窄,狭窄以上胆管扩张。光镜下:模型组胆管壁显著纤维化并增厚,胶原纤维增生明显,有较多的肌成纤维细胞并伴有炎细胞浸润,实验组胆管壁轻度增厚,成纤维细胞增殖和胶原纤维增生不明显。与模型组比较,实验1、2组肝功能损害明显减轻(P<0.05),TGF-β和PCNA表达明显降低(P<0.01);与实验2组比较,实验1组肝功能损害明显减轻(P<0.05),TGF-β和PCNA表达明显降低(P<0.01)。模型组和药物空白对照组肝功能及TGF-β、PCNA表达比较无明显差异(P>0.05)。结论电凝致胆管损伤后局部即刻应用丝裂霉素短期内可有效预防损伤后胆管狭窄,且在一定范围内该作用随药物浓度增加而增强。

Objective To explore the prophylactic effects of topical treatment with mitomycin on post-electrocoagulation stenosis of bile duct. Methods Bile duct injury model was reproduced in 38 male SD rats,the animals were then assigned into model group （n=10）,test group 1 （n=10）,test group 2 （n=10） and control group （n=8）. The injured bile ducts of the 2 test groups were wrapped with mitomycin （0.4mg/ml and 0.6mg/ml,respectively） soaked gelatin sponge for 5 minutes,while that of control group were wrapped with water for injection soaked gelatin spnge,and that of model group were left untreated. Liver function test was performed on day 15,then the animals were sacrificed. Specimens of stenosed and matched normal tissues were obtained to investigate the pathological changes and detect the expressions of transforming growth factor-beta （TGF-β） and proliferating cell nuclear antigen （PCNA）. Results Stenosis was noted at injury sites in model group on day 15,with dilation of bile duct proximal to the stenosis. Under microscope,remarkable fibrosis and notable thickening were found in bile duct wall,with an obvious proliferation of collagen fibers,and infiltration of myofibroblasts and inflammatory cells in the model group,while only slight thickening was found in bile duct wall of the 2 test groups,without significant increase in proliferation of myofibroblasts,fibrosis and collagen deposition. As compared with the model group,impairment of liver function was alleviated in the 2 test groups （P0.05）,with a decrease in expressions of TGF-β and PCNA （P0.01）. Similar changes were noted in test group 1 when compared with test group 2. No significant difference was found between the model group and the control group （P0.05）. Conclusion Instant topical application of mitomycin may affer a short period of prophylactic effects on post-electrocoagulation stenosis of bile duct in a dose-dependant manner within a certain range of concentration.