持续低温氧合机械灌注对小鼠心脏死亡器官捐献供肝的保护作用

研究体外持续低温氧合机械灌注对小鼠心脏死亡器官捐献(donation after cardiac death,DCD)供肝的保护作用.方法 雄性ICR小鼠根据灌注保存方式不同分为新鲜供肝低温保存组(FC组)、DCD供肝低温保存组(DC组)和DCD供肝低温氧合机械灌注组(DP组),每组6只.低温灌注保存供肝6h后,收集保存过供肝的威斯康星大学保存液(University of Wisconsin solution,UW液),检测丙氨酸转氨酶(ALT)和天冬氨酸转氨酶(AST)水平.收集3组小鼠肝组织,切片,行常规苏木素-伊红(HE)染色,在光学显微镜下观察病理改变,用原位末端脱氧核苷酸转移酶标记法介导的dUTP缺口末端标记(terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling,TUNEL)法观察3组小鼠肝细胞凋亡情况.结果 保存6h后,DC组与DP组的UW液中的ALT、AST含量均明显高于FC组(均为P< 0.01);DP组的ALT和AST含量均明显低于DC组(均为P< 0.01).光学显微镜下,FC组未见明显坏死区域,DC组肝细胞损伤严重,DP组肝组织未见明显损伤及坏死.荧光显微镜下,FC、DP两组肝细胞凋亡程度轻微,DC组肝细胞形态极不规则,肝细胞坏死严重.结论 持续低温氧合机械灌注可减轻肝细胞损伤和凋亡,为DCD肝移植的器官保存研究提供了新的方法.

Protective effect of continuous hypothermic oxygenated mechanical perfusion on liver graft of mice from donation after cardiac death

Objective To study protective effect of continuous hypothermic oxygenated mechanical perfusion on liver graft of mice from donation after cardiac death （DCD）. Methods According to different perfusion and storage methods, male ICR mice were divided into fresh liver/cryopreservation （FC） group, DCD liver/ cryopreservation （DC） group and DCD liver/hypothermic oxygenated mechanical perfusion （DP） group （6 mice in each group）. After hypothermic perfusion and preservation of liver grafts for 6 hours, University of Wisconsin （UW） solution was collected and the levels of alanine aminotransferase （ALT） and aspartate aminotransferase （AST） were measured. The hepatic tissues of mice in three groups were cut into sections. The pathological changes were observed by hematoxylin-eosin （HE） stain under optical microscope. The apoptosis of hepatic cell of mice in three groups was observed by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling （TUNEL）. Results After preservation for 6 hours, the contents of ALT and AST inUW solution of DC and DP group were significantly higher than those in FC group （ all in P 〈0. 01 ）. And the contents of ALT and AST in DP group were significantly lower than those in DC group （ all in P 〈 0.01 ）. Under optical microscope, no significant necrosis was observed in FC group. Severe damage of hepatic cells was observed in DC group. And no significant damage and necrosis was observed in DP group. Under fluorescence microscope, mild apoptosis of hepatic cells was observed in FC and DP group. Severe irregular shape and apoptosis of hepatic cells were observed in DC group. Conclusions Continuous hypothermic oxygenated mechanical perfusion can alleviate the damage and apoptosis of hepatic cells, which can be a new method for the study of organ preservation of DCD liver transplantation.