Tien M, Aust S D
Biochim Biophys Acta. 1982 Jul 20;712(1):1-9. doi: 10.1016/0005-2760(82)90077-7.
Rat and rabbit liver microsomes catalyze an NADPH-cytochrome P-450 reductase-dependent peroxidation of endogenous lipid in the presence of the chelate, ADP-Fe3+. Although liver microsomes from both species contain comparable levels of NADPH-cytochrome P-450 reductase and cytochrome P-450, the rate of lipid peroxidation (assayed by malondialdehyde and lipid hydroperoxide formation) catalyzed by rabbit liver microsomes is only about 40% of that catalyzed by rat liver microsomes. Microsomal lipid peroxidation was reconstituted with liposomes made from extracted microsomal lipid and purified protease-solubilized NADPH-cytochrome P-450 reductase from both rat and rabbit liver microsomes. The results demonstrated that the lower rates of lipid peroxidation catalyzed by rabbit liver microsomes could not be attributed to the specific activity of the reductase. Microsomal lipid from rabbit liver was found to be much less susceptible to lipid peroxidation. This was due to the lower polyunsaturated fatty acid content rather than the presence of antioxidants in rabbit liver microsomal lipid. Gas-liquid chromatographic analysis of fatty acids lost during microsomal lipid peroxidation revealed that the degree of fatty acid unsaturation correlated well with rates of lipid peroxidation.
在螯合剂ADP - Fe³⁺存在的情况下，大鼠和兔肝脏微粒体催化内源性脂质的NADPH - 细胞色素P - 450还原酶依赖性过氧化反应。虽然两种物种的肝脏微粒体中NADPH - 细胞色素P - 450还原酶和细胞色素P - 450的含量相当，但兔肝脏微粒体催化的脂质过氧化速率（通过丙二醛和脂质氢过氧化物的形成来测定）仅约为大鼠肝脏微粒体催化速率的40%。用从大鼠和兔肝脏微粒体中提取的微粒体脂质制成的脂质体和纯化的蛋白酶溶解的NADPH - 细胞色素P - 450还原酶重建微粒体脂质过氧化反应。结果表明，兔肝脏微粒体催化的脂质过氧化速率较低不能归因于还原酶的比活性。发现兔肝脏的微粒体脂质对脂质过氧化的敏感性要低得多。这是由于兔肝脏微粒体脂质中多不饱和脂肪酸含量较低，而不是因为存在抗氧化剂。对微粒体脂质过氧化过程中损失的脂肪酸进行气液色谱分析表明，脂肪酸不饱和度与脂质过氧化速率密切相关。
