氧自由基在高氧所致离体血管内皮细胞损伤中的作用

本实验研究了离体兔主动脉血管内皮细胞在常压高氧(100%O_2)条件下(0～72h)细胞形态、三磷酸腺苷(ATP)、黄嘌呤氧化酶(XO)活性、丙二醛(MDA)含量及谷胱甘肽过氧化物酶(GSH-px)活性的改变。我们的实验发现内皮细胞形态改变(细胞肿胀、畸形、脱落)呈时间依赖性;ATP含量经短暂的升高后(24h)持续降低(48～72h);高氧作用24～48h内皮细胞XO活性、MDA含量持续升高,72h XO活性、MDA含量开始降低,但仍高于对照组;GSH-px活性在48h内无明显改变,72h其活性升高。上述结果表明高氧确能引起内皮细胞损伤,氧自由基在其损伤过程中有重要作用。

The effects of oxygen free radicals on hyperoxia induced-damages of rabbit aortic endothelial cell

The changes of morphology, ATP and malonaldehyde (MDA) contents, xanthine oxidase (XO) activity as well as the glutathione peroxidase (GSH-px) activity of rabbit aortic endothelial cells under hyperoxia (100% O_2) for 0-72 hours were studied. We found that cellular morphological changes including swelling, shape variation after hyperoxia were time-dependent; after a temporarily increasing (24hr)(P<0.05), the level of ATP continually decreased (48-72hr)(P<0.05 or P<0.01); XO activity and MDA contents increased during 24-48hr after exposure to hyperoxia and began to decline at 72 hr (but still higher thannormal level); GSH-px activity had no significant changes until 72hr (P<0.01) after hypetoxia exposure. These results indicate that hyperoxia might cause endothelial damages in vitro and oxygen free radicals play an important role in hyperoxia-induced damages in rabbit aortic endothelial cells.