REGULATION OF PHI AND FLUID FLUX IN CORNEAL ENDOTHELIUM

清晰的视力需要光学透明的角膜。 透明度是 依赖于角膜水合作用，这是由上皮细胞控制的， 角膜内皮细胞层。 内皮控制 通过从角膜造口向房水分泌流体来水合 体液通过离子耦合流体运输。 膜和细胞 内皮细胞中转运的调节机制是其他 明白 PI的目标是开发一种内皮流体模型， 转运包括：特定的膜转运蛋白 它们的运输极性，以及运输如何 监管. 一个长期的目标是了解疾病是如何发生的，（例如富克斯的 内皮营养不良、糖尿病）改变内皮功能。 可以想象，医学疗法可以发展到延迟或取代 在内皮疾病的情况下需要角膜移植，或 外伤 由于内皮转运需要HC03和Cl，我们将 研究内皮细胞调节其 细胞内pH（pHi）、受控细胞内（C1）和C1转运 速率，使用离子敏感荧光探针测定pH、Na+、C1和 Ca2+。 转运蛋白极性将通过以下来确定： 对在可渗透过滤器上生长的细胞的测量，B）光和电子 显微镜免疫细胞化学和c）蛋白质印迹法 顶侧/基底侧膜部分。 碳酸酐酶抑制剂 缓慢内皮液体转运。 因此，我们将研究 细胞质和膜结合的碳酸酐酶在HC03中的浓度， 二氧化碳 这将通过测量HC03的影响来检验。 运输和碳酸酐酶阻断剂对未搅拌层pH 和液体运输。 因为流体输送是HC03依赖性的， 将检查pHi在确定液体转运中的作用。 这些 研究将为未来医学的发展提供基础。 治疗恢复视力的损失，可以伴随 内皮疾病或创伤。

Clear vision requires an optically transparent cornea. Transparency is dependent on corneal hydration, which is controlled by an epithelial cell layer called the corneal endothelium. The endothelium controls hydration by secreting fluid from the corneal stoma to the aqueous humor by ion coupled fluid transport. The membrane and cellular regulatory mechanisms of transport in the endothelium are ot understood. The PI's goal is to develop a model for endothelial fluid transport that includes: the specific membrane transport proteins involved, their polarity of transport, and how transport can be regulated. A long-term goal is to udnerstand how disease, (e.g. fuchs' Endothelial Dystrophy, Diabetes) alters endothelial function. Conceivable, medical therapies can be developed to delay or supplant the need for corneal transplantation in cases of endothelial disease or trauma. Since endothelial transport requires HC03 and Cl, we will examine the mechanisms by which endothelial cells regulate their intracellular pH (pHi), control intracellular (C1) and C1 transport rates, using ion sensitive fluorescent probes for pH, Na+, C1 and Ca2+. Transporter polarity will be determine by: a) physiological measurements on cells grown on permeable filters, b) light and elctron microscope immunocytochemistry and c) western blotting of apical/basolateral membrane fractions. Carbonic anhydrase inhibitors slow endothelial fluid transport. Therefore we will examine the roles of cytoplasmic and membrane bound carbonic anhydrase in HC03 to C02. This will be examined by measuring the effects of HC03 transport and carbonic anhydrase blockers on the unstirred layer pH and fluid transport. Because fluid transport is HC03 dependent, the role of pHi in determining fluid transport will be examined. These studies will provide the basis for future development of medical therapies for restoring the loss of vision that can accompany endothelial disease or trauma.