加氧低温灌流下31磷-磁共振频谱与肝酶测定在判断大鼠供肝活力中的意义

目的　探讨判断经受热缺血的肝脏活力的方法。方法　将 18只SD大鼠随机分成 3组 :A组肝脏热缺血时间 (WI)为 0min ;B组WI为 30min ;C组WI为 6 0min。各组肝脏冷保存后 2～2 .5h ,采用31磷 磁共振频谱 (31P MRS)测定各组加氧低温灌流 30min时的离体肝脏频谱 ,同时测定保存液和灌流液中肝酶的变化。结果　β 三磷酸核酸 (β NTP)与亚甲基二磷酸 (MDP)的比值 ,B组与A组比较 ,P >0 .0 5 ;C组与A、B组比较 ,P <0 .0 1。肝酶测定结果 :随着热缺血时间的延长 ,保存液中的肝酶逐渐升高 ,每组之间比较 ,差异均有显著性 (P <0 .0 5 ) ;灌流液中的肝酶 ,A组与B组比较 ,差异无显著性 (P >0 .0 5 ) ,C组与A、B两组比较 ,差异均有极显著性 (P <0 .0 1)。结论　测定加氧低温灌流下大鼠离体肝脏的ATP再生能力能较好判断其活力 ,该方法在临床热缺血供肝活力的判断上具有一定参考价值 ;同时测定保存液和灌流液中的肝酶含量 ,能配合31P MRS判断肝脏的活力。

Assessment of the viability of the rat Iiver after warm ischemic injury via 31P-MRS of the rat liver or determination of hepatic enzymes during oxygenated hypothermic reperfnsion

Objective To investigate the assessment of the viability of the donor liver after warm ischemic injury.Methods 18 SD rats were randomly and equally divided into 3 groups:A,B.C.Six rat livers were subjected to the warm ischemia 0,30 and 60 min in groups A,B and C respectively.Before reperfusion all isolated livers were stored in modified Krebs-Hensleit(mK-H)solution at 0 to 4℃for 2 to 2.5 h.Subsequently.the livers were perfused through portal vein with oxygenated cold mK-H solution for 30 to 40 min in a 31P-MRS machine while the 31P-MRS spectroscopies were carried out.The changes in liver enzymes in stored solution and perfused fluid were determined.Results The ability of ATP regeneration of rat livers in the group B was similar to group A(P＞0.05).However,in the group C,3 of 6 rat livers could not resuscitate this ability,and the average level of ATP regeneration of group C was 32.6% of the group A,which was significantly less than that in the group A and group B(P＜0.01).With the warm.ischemia prolonged,the hepatic enzymes including ALT,AST and LDH were increased gradually in stored solution with the difference being significant among the three groups(P＜0.01).There was significant difference in hepatic enzymes between group C and group A or group B(P＜0.01).Conclusions Measurement of ability of ATP regeneration of isolated rat liver after warm ischemia could be used to assess the viability of the warm ischemic livers in clinical practice.Determination of the levels of hepatic enzymes in the stored solution and the perfused solution could evaluate the hepatic viability cooperating with 3t p-MRS.