Abstract:

Objective To investigate the effect of tacrolimus on intestinal flora in donation after circulatorydeath（DCD）rats with acute rejection after liver transplantation. Methods To establish a stable normothermic machine perfusion（NMP）system. The thoracic aorta of Lewis rats was clamped for 30 minutes to obtain the DCD livers. The acute rejection model of orthotopic liver transplantation was established with brown norway（BN）rats as recipients. According to different treatment methods of liver，BN rats were divided into the following three groups ：sham operation（Sham）group，simple NMP（NMP）group and NMP combined with postoperative tacrolimus（FMP）group，with 6 rats in each group. Blood，liver and intestinal content samples were collected 14 days after operation. The liver function of blood samples was detected，the histological changes of liver were observed by HE staining，and the rejection activity index （RAI）was calculated. The intestinal contents were detected by 16SrDNA，and the changes of intestinal florastructure，diversity and function in each group were observed. Results The survival timeof ratsin FMP group（median survival time ＞ 60 d）was longer than that in NMP group（median survival time ＝ 16.5 d），and the liver function and liverhistopathology were significantly improved than those in NMP group（P ＜ 0.05）. The results of RAI showed that FMP group（2.00±1.23）was significantly lower than NMP group（7.60 ± 1.14）（P ＜ 0.05）. Compared with the NMP group，the abundance of intestinal flora in the FMP group was significantly decreased（P ＜ 0.05），and there were significant differences between the two groups. FMP group was rich in Firmicutes，Akkermansiaceae andLachnospiraceae，as well as the other glycan degradation and sphingolipid metabolism pathways.Conclusion Tacrolimus can improve liver injuryin rats withacute rejection after transplantation，andregulate the structure of intestinal flora and metabolic pathway. 

Key words:

Rat , Liver transplantation , Tacrolimus , Normothermic machineperfusion , Donation after circulatory death, Acute rejection, Intestinal flora

摘要：

目的 探讨他克莫司对心脏死亡器官捐献（donation after cardiac death，DCD）供肝移植后急性排斥反应大鼠肠道菌群的影响。 方法 构建稳定运行的常温机械灌注（normothermic machine perfusion，NMP）系统。夹闭 Lewis 大鼠胸主动脉 30 min 获取 DCD 肝脏，以棕色挪威大鼠（BN）为受体，建立原位肝移植急性排斥反应模型。根据对肝脏的不同处理方法，将 BN 大鼠分为以下 3 组 ：假手术（Sham）组、单纯NMP（NMP）组及 NMP 联合术后他克莫司（FMP）组，每组 6 只，术后 14 d 收集血液、肝脏和肠道内容物样本。血液标本检测肝功能，HE 染色观察肝脏组织学变化并计算排斥活动指数（rejection activity index，RAI），16 SrDNA 检测肠道内容物，观察各组肠道菌群结构、多样性及功能变化。 结果 FMP 组（中位生存期＞ 60 d）大鼠存活时间较 NMP 组（中位生存期为 16.5 d）延长，肝功能和肝组织病理较 NMP 组显著改善（P ＜ 0.05）。计算 RAI 结果显示，FMP 组（2.00±1.23）显著低于 NMP 组（7.60±1.14）（P ＜ 0.05）。与 NMP 组相比，FMP 组肠道菌群丰度下降，两组在物种之间有明显差异，FMP 组富含厚壁菌门、阿克曼菌科和毛螺菌科，且富集其他聚糖降解和鞘脂代谢通路。 结论 他克莫司能够改善 DCD 供肝移植后急性排斥反应大鼠肝损伤，同时调节肠道菌群结构和代谢途径。

关键词:

大鼠 , 肝移植 , 他克莫司 , 常温机械灌注 , 心脏死亡器官捐献 , 急性排斥反应 , 肠道菌群