CORNEAL ARACHIDONIC ACID METABOLISM

这项补助金的目标是确定：（1）如何花生四烯酸 (AA)正常大鼠角膜上皮中的代谢受到调节;（2）什么 角膜烧灼后花生四烯酸代谢发生变化; （3）非甾体类抗炎药是否能预防角膜炎 炎症和血管形成。 调控 将在分离的完整上皮中研究AA代谢的影响， 角膜的中性蛋白酶治疗。 细胞磷脂将是 标记有[3 H]AA和各种物质将被测试，以确定 如果它们激活磷脂酶A2并导致游离AA释放。 磷脂酶A2的激活是调节AA代谢的关键步骤 并且可能适合于药理学抑制。 另一个项目 将使用硝酸钾/银烧灼大鼠角膜， 研究AA代谢的变化发生在流入之前， 炎症细胞 将定量测定外源性[3 H]AA的代谢 此外，我们还将开发一种检测方法， L-3-磷脂酰胆碱，1-硬脂酰-2-[3 H]花生四烯酸代谢。 这些 两种互补的方法将使我们能够检测损伤引起的变化， 在磷脂酶A2活化和脂氧合酶/环氧合酶途径中 活动 最后一项研究将检查脂氧合酶的影响 抑制剂，环氧合酶抑制剂，和双 环氧合酶-脂氧合酶抑制剂对角膜炎症的作用， 大鼠角膜烧灼后的血管化。 AA的变化 炎症和血管化反应期间的代谢也将 仅使用生理盐水（药物载体）处理的动物进行研究。 这些研究将确定AA代谢物是否是重要的介质 角膜炎症和血管形成的可能性， 非甾体类药物治疗角膜炎的有效性 受伤

The objectives of this grant are to determine: (1) how arachidonic acid (AA) metabolism is regulated in normal rat corneal epithelium; (2) what changes occur in arachidonate metabolism following corneal cauterization; and (3) whether nonsteroidal anti-inflammatory drugs can prevent corneal inflammation and vascularization by inhibiting AA metabolism. Regulation of AA metabolism will be studied in intact epithelium isolated by neutral-protease treatment of corneas. Cellular phospholipids will be labeled with [3H]AA and a variety of substances will be tested to determine if they activate phospholipase A2 with resultant release of free AA. Phospholipase A2 activation is a key step in regulation of AA metabolism and is potentially amenable to pharmacological inhibition. Another project will use potassium/silver nitrate cauterization of rat corneas to investigate changes in AA metabolism occurring prior to the influx of inflammatory cells. Metabolism of exogenous [3H]AA will be quantitated and, in addition, we will develop an assay for measuring L-3-phosphatidylcholine, 1-stearoyl-2-[3H]arachidonyl metabolism. These two complimentary approaches will allow us to detect injury-induced changes in phospholipase A2 activation and lipoxygenase/cyclooxygenase pathway activity. A final study will examine the influence of lipoxygenase inhibitors, cyclooxygenase inhibitors, and a dual cyclooxygenase-lipoxygenase inhibitor on corneal inflammation and vascularization following cauterization of rat corneas. Changes in AA metabolism during the inflammatory and vascularization responses will also be studied using animals treated with normal saline (drug vehicle) only. These studies will determine whether AA metabolites are important mediators of corneal inflammation and vascularization and will clarify the potential usefulness of nonsteroidal antiinflammatory drugs for treating corneal injuries.