Abstract

The principal focus of this proposal is to investigate the ion transport mechanisms that support fluid transport by the corneal endothelium in terms of solute-solvent coupling and signaling pathways. The project will be carried out in three steps. In the first step, the mechanisms of cell volume regulation in endothelial cells subjected to acute anisosmotic perturbations will be investigated by following changes in cell volume and intracellular ionic activities. The changes in cell volume will be measured using the principles of light scattering, dye dilution and dynamic fluorescence quenching. The indicators for eye dilution technique will include transiently expressed green fluorescent protein or polar fluorescent dyes. In the second step, the modulation of cell volume regulation by signaling pathways involving second messengers and protein kinases will be identified. Finally, the maneuvers of cell signaling that induce profound changes in cell volume regulation will be employed to investigate their influence on fluid transport function by the endothelium in intact corneas. This three-step approach stems from the hypothesis that the ion transport activity and solute-solvent coupling that drive the vectorial fluid transport are mostly identical to those involved during short-term cell volume regulation. The results from this study have directly implications towards the elucidation of the mechanisms underlying fluid transport and their modulation upon long-term contract lens wear, aging, diabetes and intra-ocular surgical maneuvers.

  Funding Agency

Agency
National Institute of Health (NIH)
Institute
National Eye Institute (NEI)
Type
Research Project (R01)
Project #
5R01EY011107-05
Application #
6164684
Study Section
Visual Sciences A Study Section (VISA)
Program Officer
Fisher, Richard S
Project Start
1995-09-30
Project End
2000-05-31
Budget Start
2000-03-01
Budget End
2000-05-31
Support Year
5
Fiscal Year
2000
Total Cost
$44,333
Indirect Cost

  Institution

Name
University of California Berkeley
Department
Type
Schools of Optometry/Ophthalmol
DUNS #
094878337
City
Berkeley
State
CA
Country
United States
Zip Code
94704

  Publications

Gomes, Priya; Srinivas, Sangly P; Vereecke, Johan et al. (2005) ATP-dependent paracrine intercellular communication in cultured bovine corneal endothelial cells. Invest Ophthalmol Vis Sci 46:104-13
Gomes, Priya; Srinivas, Sangly P; Van Driessche, Willy et al. (2005) ATP release through connexin hemichannels in corneal endothelial cells. Invest Ophthalmol Vis Sci 46:1208-18
Srinivas, S P; Satpathy, M; Gallagher, P et al. (2004) Adenosine induces dephosphorylation of myosin II regulatory light chain in cultured bovine corneal endothelial cells. Exp Eye Res 79:543-51
Jans, Danny; De Weer, Paul; Srinivas, S P et al. (2002) Mg(2+)-sensitive non-capacitative basolateral Ca(2+) entry secondary to cell swelling in the polarized renal A6 epithelium. J Physiol 541:91-101
Srinivas, S P; Mutharasan, R; Fleiszig, S (2002) Shear-induced ATP release by cultured rabbit corneal epithelial cells. Adv Exp Med Biol 506:677-85
Srinivas, Sangly P; Ong, Angeline; Zhai, Chang-bin et al. (2002) Inhibition of carbonic anhydrase activity in cultured bovine corneal endothelial cells by dorzolamide. Invest Ophthalmol Vis Sci 43:3273-8
Jans, Danny; Srinivas, S P; Waelkens, Etienne et al. (2002) Hypotonic treatment evokes biphasic ATP release across the basolateral membrane of cultured renal epithelia (A6). J Physiol 545:543-55
Srinivas, Sangly P; Ong, Angeline; Goon, Leanne et al. (2002) Lysosomal Ca(2+) stores in bovine corneal endothelium. Invest Ophthalmol Vis Sci 43:2341-50
Srinivas, S P; Guan, Y; Bonanno, J A (1999) Swelling activated chloride channels in cultured bovine corneal endothelial cells. Exp Eye Res 68:165-77
Srinivas, S P; Bonanno, J A; Hughes, B A (1998) Assessment of swelling-activated Cl- channels using the halide-sensitive fluorescent indicator 6-methoxy-N-(3-sulfopropyl)quinolinium. Biophys J 75:115-23

Showing the most recent 10 out of 12 publications