Schjøtt J, Brekke O L, Jynge P, Bjerve K S, Hamazaki T
Department of Pharmacology and Toxicology, University Medical Center, University of Trondheim, Norway.
Scand J Clin Lab Invest. 1993 Dec;53(8):873-82. doi: 10.3109/00365519309086501.
The aim of the present study was to examine the effect of acute infusion of lipid emulsions enriched with either docosahexaenoic acid (DHA) or eicosapentaenoic acid (EPA) on heart lipids, tolerance to infusion and to ischaemia-reperfusion. Isolated rat hearts were subjected to a 10 min lipid infusion period prior to 25 min of total global ischaemia and 30 min of reperfusion. Effects on physiology and metabolism were recorded during infusion and reperfusion. A more than doubled increase of DHA and a 12-fold increase of EPA in terms of relative concentration was demonstrated in the free fatty acid fraction after infusion with the respective triglyceride emulsions, without any profound change in physiology. High levels of DHA were associated with a reduced recovery of left ventricular developed pressure (LVDP) and increased release of lactate dehydrogenase (LDH) during reperfusion, while the hearts infused with the EPA-emulsion showed a recovery comparable to the control group. Heart lipid peroxidation, evaluated by release of thiobarbituric acid reactive substances (TBARS) in effluate, was about 4-fold higher in the DHA-group compared to the EPA-group during start of reperfusion and may in part explain the reduced recovery observed in these hearts. The present study demonstrates enrichment of DHA and EPA in the free fatty acid fraction after a short period of infusion. Protective effects of the emulsions were not found, instead the data indicate harmful effects of DHA during ischaemia-reperfusion. However, the presence of TBARS in this emulsion could have influenced the results.
本研究的目的是检测急性输注富含二十二碳六烯酸（DHA）或二十碳五烯酸（EPA）的脂质乳剂对心脏脂质、输注耐受性及缺血再灌注的影响。离体大鼠心脏在经历25分钟全心缺血和30分钟再灌注之前，先进行10分钟的脂质输注。在输注和再灌注期间记录对生理和代谢的影响。分别输注甘油三酯乳剂后，游离脂肪酸部分中DHA的相对浓度增加了一倍多，EPA增加了12倍，且生理方面无任何显著变化。高水平的DHA与再灌注期间左心室舒张末压（LVDP）恢复降低及乳酸脱氢酶（LDH）释放增加有关，而输注EPA乳剂的心脏显示出与对照组相当的恢复情况。通过流出液中硫代巴比妥酸反应性物质（TBARS）释放评估的心脏脂质过氧化，在再灌注开始时，DHA组比EPA组高约4倍，这可能部分解释了这些心脏中观察到的恢复降低情况。本研究表明，短时间输注后游离脂肪酸部分中DHA和EPA含量增加。未发现乳剂的保护作用，相反，数据表明DHA在缺血再灌注期间有有害作用。然而，该乳剂中TBARS的存在可能影响了结果。
