Hurst J S, Paterson C A, Short C S
Kentucky Lions Eye Research Institute, Department of Ophthalmology, University of Louisville Medical School.
J Ocul Pharmacol. 1989 Spring;5(1):51-64. doi: 10.1089/jop.1989.5.51.
Ocular tissues have the capacity to metabolize arachidonate to prostaglandins and related materials, such as hydroxy arachidonate derivatives (HETEs) which are potent mediators of the inflammatory response. Reactive oxygen species are also present during the inflammatory response, resulting in an altered oxidative environment within the eye. This study was designed to evaluate the possible impact of the oxidant hydrogen peroxide and anti-oxidants, ascorbic acid and glutathione, upon arachidonate metabolism. It was found that hydrogen peroxide was observed to potently inhibit arachidonate metabolism in the cornea, but not in the iris-ciliary body. This might be related to a more efficient detoxification of hydrogen peroxide by iris-ciliary body. Ascorbate appeared to have a general stimulatory influence upon arachidonate metabolism in the iris-ciliary body. In the cornea, ascorbate selectively reduced metabolism to HETE while enhancing the products generated by the cyclo-oxygenase pathway. In both cornea and iris-ciliary body reduced glutathione suppressed conversion of arachidonate to its active metabolites. These observations indicate that arachidonate metabolism in ocular tissues is sensitive to the oxidative environment.
眼部组织有能力将花生四烯酸代谢为前列腺素及相关物质，如羟基花生四烯酸衍生物（HETEs），它们是炎症反应的强效介质。炎症反应期间也会产生活性氧，导致眼内氧化环境改变。本研究旨在评估氧化剂过氧化氢以及抗氧化剂维生素C和谷胱甘肽对花生四烯酸代谢的可能影响。研究发现，过氧化氢可有效抑制角膜中的花生四烯酸代谢，但对虹膜睫状体无此作用。这可能与虹膜睫状体对过氧化氢更有效的解毒作用有关。维生素C似乎对虹膜睫状体中的花生四烯酸代谢具有普遍的刺激作用。在角膜中，维生素C选择性地减少了向HETE的代谢，同时增强了环氧化酶途径产生的产物。在角膜和虹膜睫状体中，还原型谷胱甘肽均抑制花生四烯酸向其活性代谢物的转化。这些观察结果表明，眼部组织中的花生四烯酸代谢对氧化环境敏感。
