ION CURRENT ANALYSIS IN THE CORNEA

角膜中的离子电流分析

基本信息

批准号：
3262320
负责人：
Larry S. Liebovitch
金额：
$ 8.54万
依托单位：
COLUMBIA UNIV NEW YORK MORNINGSIDE
依托单位国家：
美国
项目类别：
财政年份：
1986
资助国家：
美国
起止时间：
1986-07-01 至 1989-06-30
项目状态：
已结题

项目摘要

The corneal endothelium maintains the transparency of the cornea by transporting ions and fluid out of the corneal stroma to maintain the low level of hydration required for transparency. We propose to study the mechanisms of this transport to better understand the normal physiology of transport and thus how it is altered in disease. Transendothelial electrical potential difference, short circuit current, radioactive fluxes, and intracellular microelectrodes all measure ion flows through multiple pathways in the cell membrane simultaneously. Thus, the interpretation of those experimental results is often very complex and sometimes ambiguous. However, the recently invented patch clamp technique can measure the flows of ions through a single molecule, one pore in the cell membrane, and thus avoid these uncertainties. Unfortunately the patch clamp technique is now limited because 1) it takes a very long time to analyze the experimental data, 2) only patches with one pore can be used to measure pore kinetics, and 3) it cannot detect carriers (symports and antiports) or ion pumps (such as the soidum-potassium ATPase). We will overcome these limitations by designing and testing new mathematical techniques that will be able to 1) measure the kinetics of pores in patch clamp data much faster and more simply, 2) determine complex pore kinetics, 3) detect and measure net rates of cyclic pores, 4) extract kinetic data from patches with more than one pore, 5) identify pore-pore interactions, 6) study non-stationary kinetics, and 7) provide ways that ion pumps carriers and pumps could be measured using the patch clamp technique.

角膜内皮维持角膜的透明度通过将离子和液体输送出角膜基质来输送角膜以维持所需的低水合作用水平透明度。我们建议研究这一机制运输以更好地了解正常生理机能运输以及它在疾病中如何改变。跨内皮电位差、短路电流、放射性通量和细胞内微电极所有测量离子流经细胞内的多个路径同时膜。因此，这些的解释实验结果往往非常复杂，有时模糊的。然而，最近发明的膜片钳该技术可以测量通过单个分子，细胞膜上的一个孔，从而避免这些不确定性。不幸的是，膜片钳技术现在受到限制，因为 1）分析实验数据需要很长时间， 2) 只能使用具有一个毛孔的贴片来测量毛孔动力学，3）它无法检测载体（symports和反向端口）或离子泵（例如钠钾 ATP 酶）。我们将通过设计和测试新产品来克服这些限制数学技术能够 1）测量膜片钳数据中孔的动力学更快、更多简而言之，2) 确定复杂的孔隙动力学，3) 检测和测量循环孔的净速率，4) 从具有多个孔的斑块，5) 识别孔-孔相互作用，6) 研究非平稳动力学，以及 7) 提供离子泵载流子和泵的测量方法膜片钳技术。