Ciliary body control of organic anions in the aqueous humor of the eye

睫状体对眼房水中有机阴离子的控制

• 批准号: 418243-2012
• 负责人: Pelis, Ryan
• 金额: $ 1.82万
• 依托单位: Dalhousie University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2015
• 资助国家: 加拿大
• 起止时间: 2015-01-01 至 2016-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=573554
• 关键词: Ciliary; body; control; organic; anions

Aqueous humor is the transparent fluid surrounding the lens that helps maintain the shape and optical properties of the eye. Aqueous humor is produced by the ciliary body epithelium, a sheet of cells that separates the bloodstream from the aqueous compartment. The concentration of a number of organic anions, such as uric acid, is lower in aqueous humor than plasma, suggesting that they are actively removed. Organic anions represent a relatively broad class of chemicals, including hormones, metabolic intermediates, drugs and environmental contaminants, which in excess can disrupt normal biological processes. The ability to control aqueous humor concentrations of organic anions is of particular importance to the lens, as this tissue has no blood supply. The ciliary body epithelium, being in contact with both the blood supply and aqueous humor, is uniquely positioned to regulate the chemical composition of the aqueous humor. Given that organic anions are relatively impermeable to plasma membranes their efficient movement across ciliary body epithelial cells requires facilitation by membrane transport proteins (organic anion transporters) as well as the input of cellular energy. The aims of this proposal are: 1) to show that the ciliary body epithelium is capable of transporting organic anions in the aqueous humor-to-blood direction and to define the energetic requirements; 2) to determine which organic anion transporters are present in the ciliary body epithelium and where they are expressed; and 3) to identify which of the organic anion transporters are involved in the transport process by specifically inhibiting them. The aims outlined in this proposal support the long-term objective of this research program, which is to understand the processes that regulate the chemical composition of the aqueous humor, a saline vital for vision.

水状体是围绕透镜的透明液体，其有助于维持眼睛的形状和光学性质。 眼房水由睫状体上皮细胞产生，睫状体上皮细胞是将血流与水室分开的细胞片。 许多有机阴离子的浓度，如尿酸，在房水中低于血浆，表明它们被主动清除。 有机阴离子代表了一个相对广泛的化学品类别，包括激素，代谢中间体，药物和环境污染物，过量会破坏正常的生物过程。 控制有机阴离子的房水浓度的能力对于透镜是特别重要的，因为该组织没有血液供应。 睫状体上皮细胞与血液供应和房水两者接触，被独特地定位以调节房水的化学组成。 考虑到有机阴离子对质膜相对不可渗透，它们跨睫状体上皮细胞的有效移动需要膜转运蛋白（有机阴离子转运蛋白）的促进以及细胞能量的输入。 该建议的目的是：1）显示睫状体上皮能够在水体液到血液方向上运输有机阴离子，并确定能量需求; 2）确定睫状体上皮中存在哪些有机阴离子转运蛋白以及它们在哪里表达;和3）通过特异性抑制有机阴离子转运蛋白来鉴定哪些有机阴离子转运蛋白参与转运过程。 该提案中概述的目标支持该研究计划的长期目标，即了解调节眼房水化学成分的过程，眼房水是一种对视力至关重要的盐水。