Takayama F, Egashira T, Kudo Y, Yamanaka Y
Department of Pharmacology, Oita Medical University, Japan.
Biochem Pharmacol. 1993 Nov 17;46(10):1749-57. doi: 10.1016/0006-2952(93)90579-l.
The present study set out to investigate whether plasma phosphatidylcholine hydroperoxide (PCOOH) levels could accurately reflect lipid peroxidation linking to liver damage due to ischemia--reperfusion. PCOOH is a primary peroxidative product of phosphatidylcholine (PC), which is the most important functional lipid in the hepatocellular membrane, and may mediate oxidative stress. We quantified PCOOH and PC in the plasma and liver of rats subjected to hepatic ischemia-reperfusion by chemiluminescence detecting HPLC (CL-HPLC) method. Plasma PCOOH levels showed no significant rise in either the ischemia only group or in the sham-operation group, compared to controls (0.7 nmol/mL plasma). At 60 min subsequent to reperfusion, the PCOOH levels in plasma and liver, as well as the levels of several serum markers of liver injury [lactic dehydrogenase (LDH), glutamic-oxalacetic transaminase (GOT), glutamic-pyruvic transaminase (GPT)] increased in proportion to the duration of ischemia (up to 60 min). During periods of reperfusion following 30 min of ischemia, plasma PCOOH increased biphasically (2 nmol/mL; 12-24 hr duration of reperfusion), and generally ran parallel to that in the liver after more than 60 min of reperfusion. Dose-dependent protective effects against warm ischemia (30 min)-reperfusion (12 hr) injury were clearly demonstrated in the groups treated with allopurinol, diclofenac Na, ascorbic acid (V.C), alpha-tocopherol and coenzyme Q10, but not in those treated with r-h-superoxide dismutase or betamethasone. The rises in plasma PCOOH and serum GOT, GPT and LDH of the ischemia-reperfused rats were ameliorated most in the group pretreated with diclofenac Na, and next most in the group pretreated with V.C. These results indicate that the plasma PCOOH levels are a useful index both for liver cell damage induced by oxygen free radicals generated during ischemia-reperfusion, and to investigate the efficacy of drugs against oxidative stress.
本研究旨在探讨血浆磷脂酰胆碱氢过氧化物（PCOOH）水平是否能准确反映与缺血再灌注所致肝损伤相关的脂质过氧化。PCOOH是磷脂酰胆碱（PC）的主要过氧化产物，而PC是肝细胞膜中最重要的功能脂质，且可能介导氧化应激。我们采用化学发光检测高效液相色谱法（CL-HPLC）对遭受肝缺血再灌注的大鼠血浆和肝脏中的PCOOH及PC进行定量分析。与对照组（血浆0.7 nmol/mL）相比，单纯缺血组和假手术组的血浆PCOOH水平均未显著升高。再灌注60分钟后，血浆和肝脏中的PCOOH水平以及几种肝损伤血清标志物[乳酸脱氢酶（LDH）、谷草转氨酶（GOT）、谷丙转氨酶（GPT）]的水平随缺血时间（最长60分钟）成比例增加。在缺血30分钟后的再灌注期间，血浆PCOOH呈双相增加（2 nmol/mL；再灌注持续12 - 24小时），且在再灌注60分钟后通常与肝脏中的情况平行。用别嘌呤醇、双氯芬酸钠、抗坏血酸（维生素C）、α-生育酚和辅酶Q10治疗的组对热缺血（30分钟）-再灌注（12小时）损伤具有明显的剂量依赖性保护作用，而用重组人超氧化物歧化酶或倍他米松治疗的组则无此作用。双氯芬酸钠预处理组中缺血再灌注大鼠的血浆PCOOH以及血清GOT、GPT和LDH的升高改善最为明显，其次是维生素C预处理组。这些结果表明，血浆PCOOH水平既是缺血再灌注过程中产生的氧自由基所致肝细胞损伤的有用指标，也是研究抗氧化应激药物疗效的有用指标。
