Fusai Giuseppe, Glantzounis George K, Hafez Tarek, Yang Wenxuan, Quaglia Alberto, Sheth Hemant, Kanoria Sanjeev, Parkes Harry, Seifalian Alexander, Davidson Brian R
University Department of Surgery and Liver Transplant Unit, Royal Free Hospital, Royal Free and University College Medical School, Pond Street, London NW3 2QG, U.K.
Clin Sci (Lond). 2005 Nov;109(5):465-73. doi: 10.1042/CS20050081.
Steatotic livers are highly susceptible to I/R (ischaemia/reperfusion) injury and, therefore, the aim of the present study was to evaluate the in vivo effect of NAC (N-acetylcysteine) on hepatic function in the early and initial late phase of warm liver I/R injury in steatotic rabbits. Twelve New Zealand White rabbits were fed a high-cholesterol (2%) diet. The control group (n=6) underwent lobar liver ischaemia for 1 h, followed by 6 h of reperfusion. In the treated group receiving NAC (n=6), an intravenous infusion of NAC was administered prior to and during the 6 h reperfusion period. Systemic and hepatic haemodynamics were monitored continuously. ALT (alanine aminotransferase) activity and bile production were measured. NMR spectroscopy was used to analyse bile composition. Oxidation of DHR (dihydrorhodamine) to RH (rhodamine) was used as a marker of production of reactive oxygen and nitrogen species. Moderate centrilobular hepatic steatosis was demonstrated by histology. The results showed that NAC administration significantly improved portal flow, hepatic microcirculation, bile composition and bile flow after 5 h of reperfusion. NAC administration was also associated with less hepatocellular injury, as indicated by ALT serum activity, and decreased the oxidation of DHR to RH. In conclusion, NAC administration decreased the extent of I/R injury in the steatotic liver, particularly during the late phase of reperfusion.
脂肪变性的肝脏对缺血/再灌注(I/R)损伤高度敏感,因此,本研究的目的是评估N-乙酰半胱氨酸(NAC)对脂肪变性兔温肝I/R损伤早期和再灌注初期肝功能的体内作用。12只新西兰白兔喂食高胆固醇(2%)饮食。对照组(n=6)进行肝叶缺血1小时,随后再灌注6小时。在接受NAC治疗的组(n=6)中,在6小时再灌注期之前和期间静脉输注NAC。连续监测全身和肝脏血流动力学。测量丙氨酸氨基转移酶(ALT)活性和胆汁生成。利用核磁共振波谱分析胆汁成分。二氢罗丹明(DHR)氧化为罗丹明(RH)用作活性氧和氮物种产生的标志物。组织学显示中度小叶中央性肝脂肪变性。结果表明,再灌注5小时后,给予NAC显著改善门静脉血流、肝微循环、胆汁成分和胆汁流量。如ALT血清活性所示,给予NAC还与肝细胞损伤减轻有关,并减少了DHR氧化为RH。总之,给予NAC可减轻脂肪变性肝脏的I/R损伤程度,尤其是在再灌注后期。