氟橡胶246B制成仿生阀门人工胆管植入犬体内的生物学效应

Biological effect of artificial bile duct combined with bionic valve made by fluoroelastomers-246B following implantation in dogs

背景:寻找合适的材料并制作成能与人体正常生理功能相契合的人工胆道目前需要解决两个问题,即材料选取与仿生阀门的定向开放。目的:观察氟橡胶246B制成的具有仿生阀门的人工胆管植入犬体内后的生物学特性,分析其作为胆道替代物的可行性。设计、时间及地点:材料学体内对照观察,于2007-10/2008-10在吉林大学超分子结构与材料教育部重点实验室、吉林大学第一医院外科实验室完成。材料:雄性杂交犬12只,按随机区组原则分为普通直管组、带瓣膜直管组、带活瓣直管组,4只/组。氟橡胶246B购于扬中市橡胶塑料厂。方法:将氟橡胶246B溶于四氢呋喃后重新塑形,制成长3.0cm、半径0.5cm的普通直管;带瓣膜直管的管壁内带有3个类似静脉瓣的瓣膜结构,按胆汁定向流动起到抗返流作用;带活瓣直管在管道一端套以管形橡胶薄膜,发挥单向活瓣作用。各组犬麻醉后,切开肝十二指肠韧带浆膜层显露游离胆总管,将胆总管末端以丝线结扎横断,分别将3种人工胆管植入犬体内,生存30d后处死。主要观察指标:肝功能指标的变化,管道通畅性及抗返流情况,胆囊的炎症反应。结果:12只犬均进入结果分析。与术前1d比较,术后7d各组血清总胆红素、丙氨酸氨基转移酶、门冬氨酸氨基转移酶含量均无明显变化(P>0.05);术前1d及术后7d时,上述各指标组间比较亦无明显差异(P>0.05)。术后30d普通直管组处于半瘀塞状态,管道壁有较多黄绿色沉淀物;带瓣膜直管组瓣膜上方管壁略成黄绿色沉淀物,管腔内少许白色絮状物,瓣膜上无明显沉淀物;带活瓣直管组靠近活瓣的胆管壁有少许黄绿色沉淀物,胆汁内混有少许白色絮状物。术后30d普通直管组黏膜上皮不完整,有腺体的轻度增生;带瓣膜直管组黏膜上皮尚完好,未见明显腺体增生;带活瓣直管组黏膜上皮保持完好,腺上皮细胞无异型性。

BACKGROUND： Both material selection and directional opening of bionic valve need to be solved in order to establish an artificial bile duct which is coincidence to normal physiological function of human body. OBJECTIVE： To explore the biological characteristics of artificial bile duct combined with bionic valve made by made by fluoroelastomer-246B which was implanted into dogs, and to analyze the feasibility as a substitute of biliary tract. DESIGN, TIME AND SETTING： An in vivo materials contrast experiment was performed at Key Laboratory of Supramolecular Structure and Materials of Jilin University and Surgical Laboratory of the First Hospital of Jilin University from October 2007 to October 2008. MATERIALS： Twelve male dogs in hybridization were randomly divided into straight tube group, venous valve tube group, and living valve tube group, with 4 dogs in each group. Fluoroelastomer-246B was provided by Yangzhong Rubber and Plastics Factory. METHODS： Fluoroelastomer-246B was dissolved in tetrahydrofuran to make two straight-tube-like ducts with 3.0 cm in length and 0.5 cm in diameter： the first one with three valve structure like venous valve playing a role of anti-reflux, the second one with a tubular rubber valve at the end of pipeline playing the role of one-way living valve. By anesthesia, placenta percreta of hepatoduodenal ligament was cut open to expose free common bile duct whose terminal was ligated using thread. The three kinds of artificial bile ducts were implanted into dogs, respectively, and then dogs were sacrificed after 30 days. MAIN OUTCOME MEASURES： Changes of hepatic function, patency and anti-reflux of bile duct, and inflammatory reaction of gallbladder. RESULTS： A total of 12 dogs were included in the final analysis. Levels of serum total bilirubin, alanine aminotransferase, and aspartate aminotransferase were not changed at day 7 after operation compared to day 1 before operation （P 〉 0.05）. There were also no significant differences in the above-mentioned indicators at day 1 before operation and at day 7 after operation in each group （P 〉 0.05）. At day 30 after operation, half-pipe blockage occurred, and some yellow-green sediments were observed on the pipe wall in the straight tube group; a few of yellow-green sediments were found at top of wall, and some white floc sediments were observed in lumen but nothing was observed on valve in the venous valve tube group; a few of yellow-green sediments were found on pipe wall near the living valve, and some white floc sediments were observed in bile in the living valve tube group. At day 30 after operation, epithelium of mucous membrane was not intact, and gland proliferated lightly in the straight tube group; epithelium of mucous membrane was generally intact, and proliferation of gland was not found in the venous valve tube group; epithelium of mucous membrane was exactly intact, and glandular epithelial cells were not heteromorphism in the living valve tube group. CONCLUSION： The artificial bile ducts with a valve structure and living value structure has a good patency and plays an effective role of anti-reflux after a short-term observation, suggesting that a valve structure acts as a similar function to Oddis sphincter.