TRACE ELEMENT DYNAMICS IN THE VERTEBRATE EYE

脊椎动物眼中的微量元素动态

• 批准号: 3259504
• 负责人: MARY C McGahan
• 金额: $ 11.09万
• 依托单位: NORTH CAROLINA STATE UNIVERSITY RALEIGH
• 依托单位国家: 美国
• 财政年份: 1986
• 资助国家: 美国
• 起止时间: 1986-04-01 至 1989-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3259504
• 关键词: Chordata; L ascorbate oxidase; antiinflammatory agents; antioxidants; ascorbate; atomic absorption spectrometry; blood aqueous barrier; blood proteins; cataract; copper; dietary trace element; eye infections; eye pharmacology; ferroxidase; glutathione peroxidase; high performance liquid chromatography; immunochemistry; inflammation; intraocular fluid; iron; selenium; serotonin; trace elements; transferrin; transport proteins; uveitis

The concentrations of copper (Cu), iron (Fe) and selenium (Se) in the intraocular fluids (IOFs) and plasma of a number of mammalian species have been determined by electrothermal atomic absorption spectrophotometry (EAAS) using methods developed in an ongoing project. The plasma contains considerably higher concentrations of these elements than the IOFs. In plasma almost all of the Cu is bound to the alpha 2-globulin, ceruloplasmin, Fe is bound to transferrin and Se to glutathione peroxidase. During ocular inflammation in rabbits, the aqueous humor concentration of all these elements increase in parallel to the increase in protein concentration, most likely due to the influx of plasma proteins when the blood-aqueous barrier is disrupted. Although these proteins are effective anti-oxidants and may play an important role in the inflammatory response and other disease states, their possible roles in ocular inflammation and disease have not been studied. For example, ceruloplasmin can oxidize a number of substrates, including serotonin and ascorbic acid; interaction with the latter is histaminolytic. The ferroxidase activity of this protein can protect against iron damage by catalyzing high affinity binding of ferric ions to transferrin. Glutathione peroxidase can inactivate hydrogen peroxide. Although it is assumed that the increase in trace element concentration in the IOFs during inflammation is due to the influx of plasma proteins, this has not been proven. In addition transferrin and ceruloplasmin may release the Cu and Fe, which they carry, upon entering the IOFs. In order to determine whether these elements enter the IOFs bound to their carrier proteins, and their subsequent fate, a method has been developed for separation of proteins by molecular weight using HPLC gel filtration and analysis of the resulting fractions for trace element content using EAAS. The technique will be applied to an analysis of the IOFs from normal and inflamed eyes of rabbits and normal and diseased eyes of various animal species treated in our ophthalmology clinic and surgery classes (species include: dogs, cats, cows, sheep, pigs, horses, ponies, etc.). Furthermore, the activities of the plasma proteins which may be present in the IOFs under these conditions will be measured with a view to determining what role (e.g. beneficial or detrimental) they may play in the ocular response to injury, inflammation and disease.

铜（Cu）、铁（Fe）和硒（Se）的浓度 许多哺乳动物物种的眼内液（IOF）和血浆具有 电热原子吸收分光光度法测定 (EAAS) 使用正在进行的项目中开发的方法。 血浆中含有 这些元素的浓度比 IOF 高得多。 在 血浆中几乎所有的 Cu 都与 α2-球蛋白结合， 铜蓝蛋白、Fe 与转铁蛋白结合、Se 与谷胱甘肽结合 过氧化物酶。 在兔子眼部炎症期间，房水 所有这些元素的浓度随着 蛋白质浓度，很可能是由于血浆蛋白的流入 当血水屏障被破坏时。 虽然这些蛋白质 有效的抗氧化剂，可能在炎症中发挥重要作用 反应和其他疾病状态，它们在眼部的可能作用 炎症和疾病尚未被研究。 例如，铜蓝蛋白 可以氧化多种底物，包括血清素和抗坏血酸； 与后者的相互作用是组织胺溶解的。 亚铁氧化酶活性 这种蛋白质可以通过催化高亲和力来防止铁损伤 三价铁离子与转铁蛋白的结合。 谷胱甘肽过氧化物酶可以 使过氧化氢失活。 尽管假设增加 炎症期间 IOF 中的微量元素浓度是由于 血浆蛋白的流入，这一点尚未得到证实。 此外 转铁蛋白和铜蓝蛋白可能会释放它们携带的铜和铁， 进入 IOF 后。 为了判断这些元素是否进入 IOF 与其载体蛋白结合，以及它们随后的命运，a 已开发出按分子量分离蛋白质的方法 使用 HPLC 凝胶过滤并对所得级分进行痕量分析 使用 EAAS 测定元素含量。 该技术将应用于分析 兔子正常眼睛和发炎眼睛的 IOF 以及正常和发炎眼睛的 IOF 在我们的眼科诊所治疗各种动物的患病眼睛 和外科课程（物种包括：狗、猫、牛、羊、猪、 马、小马等）。 此外，血浆蛋白的活性 在这些条件下 IOF 中可能存在的物质将被测量 以确定它们的作用（例如有益或有害） 可能在眼部对损伤、炎症和疾病的反应中发挥作用。