Prasad K, Kalra J
Department of Physiology, College of Medicine, University of Saskatchewan, Saskatoon, Canada.
Am Heart J. 1993 Apr;125(4):958-73. doi: 10.1016/0002-8703(93)90102-f.
We investigated the effects of a high-cholesterol diet in the presence and absence of vitamin E on the lipid peroxidation product malondialdehyde of blood and aortic tissue, the oxygen-free-radical-producing activity of polymorphonuclear leukocytes (PMNs) (PMN chemiluminescence), and the blood lipid profile in rabbits. The animals were divided into four groups each of which comprised 10 rabbits. Rabbits in group I received a regular rabbit chow diet; those in group II received vitamin E; those in group III received high cholesterol + vitamin E; and those in group IV received a high-cholesterol diet. Blood concentrations of triglycerides, total cholesterol, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), very low-density lipoprotein cholesterol (VLDL-C), malondialdehyde, and PMN chemiluminescence were measured. The aorta of each rabbit was removed at the end of the protocol for assessment of atherosclerotic changes (gross and microscopic) and malondialdehyde. Serum triglycerides, total cholesterol, HDL-C, LDL-C, and VLDL-C increased while HDL/LDL ratio decreased in groups III and IV but remained unchanged in group I. There was an increase in the HDL-C component and HDL/LDL ratio and a decrease in the LDL-C component and triglycerides in group II. Blood and aortic tissue malondialdehyde increased in group IV but decreased in groups II and III. PMN chemiluminescence increased in groups III and IV. Atherosclerotic changes were marked in group IV as compared with those in group III. However, histologic changes in the aortas were similar in groups III and IV. The increased levels of blood and aortic tissue malondialdehyde and PMN chemiluminescence, which were associated with development of atherosclerosis, suggest a role of oxygen free radicals in the pathogenesis of hypercholesterolemia-induced atherosclerosis. The protection afforded by vitamin E, which was associated with a decrease in blood and aortic tissue malondialdehyde concentration in spite of hypercholesterolemia, supports the hypothesis that oxygen free radicals are involved in the development of hypercholesterolemic atherosclerosis.
我们研究了在有和没有维生素E的情况下，高胆固醇饮食对兔血液和主动脉组织中脂质过氧化产物丙二醛、多形核白细胞（PMN）产生氧自由基的活性（PMN化学发光）以及血脂谱的影响。将动物分为四组，每组10只兔。第一组兔给予常规兔饲料；第二组兔给予维生素E；第三组兔给予高胆固醇+维生素E；第四组兔给予高胆固醇饮食。测量了甘油三酯、总胆固醇、低密度脂蛋白胆固醇（LDL-C）、高密度脂蛋白胆固醇（HDL-C）、极低密度脂蛋白胆固醇（VLDL-C）、丙二醛和PMN化学发光的血液浓度。在实验方案结束时，取出每只兔的主动脉，用于评估动脉粥样硬化变化（大体和显微镜下）以及丙二醛。第三组和第四组血清甘油三酯、总胆固醇、HDL-C、LDL-C和VLDL-C升高，而HDL/LDL比值降低，第一组则保持不变。第二组HDL-C成分和HDL/LDL比值升高，LDL-C成分和甘油三酯降低。第四组血液和主动脉组织丙二醛增加，而第二组和第三组降低。第三组和第四组PMN化学发光增加。与第三组相比，第四组动脉粥样硬化变化明显。然而，第三组和第四组主动脉的组织学变化相似。血液和主动脉组织丙二醛水平以及PMN化学发光增加与动脉粥样硬化的发展相关，这表明氧自由基在高胆固醇血症诱导的动脉粥样硬化发病机制中起作用。尽管存在高胆固醇血症，但维生素E提供的保护与血液和主动脉组织丙二醛浓度降低相关，这支持了氧自由基参与高胆固醇血症性动脉粥样硬化发展的假说。
