Minor T, Isselhard W, Yamamoto Y, Obara M, Saad S
Institute for Experimental Medicine University of Cologne, Köln, Germany.
Surg Today. 1993;23(8):728-32. doi: 10.1007/BF00311713.
This study was aimed at examining the vulnerability of the liver to oxygen-free radicals upon reoxygenation after prolonged ischemia. Livers from male Wistar rats were first flushed with Ringer's and Euro-Collins solutions. After ischemic storage in Krebs-Henseleit solution at 37 degrees C for 60 min and in Euro-Collins solution at 4 degrees C for another 60 min, they were then persufflated with either gaseous O2 or N2 for 30 min at 37 degrees C, and rinsed again with Ringer's solution. Enzyme concentrations and calcium ion activities were measured in the effluent rinsing solution after passage through the liver. Treatment with superoxide dismutase (SOD) or allopurinol resulted in a significant reduction of tissue injury, determined by the enzyme loss, calcium uptake, and lipid peroxidation upon persufflation with O2. Allopurinol also improved the tissue levels of ATP and the sum of adenine nucleotides after aerobic persufflation, whereas SOD did not. Notwithstanding, neither treatment had any effect on anoxic persufflation with N2. Thus, we conclude that the postischemic liver is susceptible to oxygen-induced free radical injury and that allopurinol and SOD promote specific antioxidative protection of the liver, with the exclusion of side effects related to substrates or perfusion modalities.
本研究旨在探讨长时间缺血后复氧时肝脏对氧自由基的易损性。取自雄性Wistar大鼠的肝脏先用林格氏液和欧洲柯林斯液冲洗。在37℃的克雷布斯-亨泽莱特溶液中缺血保存60分钟，然后在4℃的欧洲柯林斯溶液中再保存60分钟，之后在37℃用气态O₂或N₂吹入30分钟，再用林格氏液冲洗。测量肝脏流出的冲洗液中的酶浓度和钙离子活性。用超氧化物歧化酶（SOD）或别嘌呤醇处理可使组织损伤显著减轻，组织损伤通过吹入O₂时的酶流失、钙摄取和脂质过氧化来确定。别嘌呤醇还能提高有氧吹入后组织中的ATP水平和腺嘌呤核苷酸总量，而SOD则不能。然而，两种处理对用N₂进行的无氧吹入均无影响。因此，我们得出结论，缺血后肝脏易受氧诱导的自由基损伤，别嘌呤醇和SOD可促进肝脏的特异性抗氧化保护，且排除了与底物或灌注方式相关的副作用。
