This proposal examines the hypothesis that a majority of aqueous outflow resistance is due to an accumulation of macromolecules in the extracellular spaces of the juxtacanalicular connective tissue and further, that certain components of this resistance- causing material are contained in aqueous humor. We anticipate that confirmation of these hypothesis will identify factors which lead to elevated intraocular pressure and glaucoma. Our group found that macromolecules present in aqueous humor dramatically affect the resistance to flow through microporous filters with pore dimensions similar to those of the juxtacanalicular meshwork. These macromolecules interact hypdophobically with the microporous filters and it is postulated that a similar interaction may occur in the juxtancanalicular connective tissue. The distribution of these macromolecules in the aqueous outflow system will be determine morphologically. A model is being developed that both theoretically and experimentally characterizes the permeability of the extracellular matrix gel that presumably fills the open spaces of the juxtacanalicular connective tissue. This model will be used to analyze the causes of primary open-angle glaucoma and pigmentary glaucoma.

Agency
National Institute of Health (NIH)
Institute
National Eye Institute (NEI)
Type
Research Project (R01)
Project #
5R01EY005503-07
Application #
3260631
Study Section
Visual Sciences A Study Section (VISA)
Project Start
1984-07-01
Project End
1992-06-30
Budget Start
1990-07-01
Budget End
1991-06-30
Support Year
7
Fiscal Year
1990
Total Cost
Indirect Cost
Name
Massachusetts Institute of Technology
Department
Type
Schools of Engineering
DUNS #
City
Cambridge
State
MA
Country
United States
Zip Code
02139
Johnson, M; Shapiro, A; Ethier, C R et al. (1992) Modulation of outflow resistance by the pores of the inner wall endothelium. Invest Ophthalmol Vis Sci 33:1670-5
Johnson, M; Johnson, D H; Kamm, R D et al. (1990) The filtration characteristics of the aqueous outflow system. Exp Eye Res 50:407-18
Ethier, C R; Kamm, R D; Johnson, M et al. (1989) Further studies on the flow of aqueous humor through microporous filters. Invest Ophthalmol Vis Sci 30:739-46
Pavao, A F; Lee, D A; Ethier, C R et al. (1989) Two-dimensional gel electrophoresis of calf aqueous humor, serum, and filter-bound proteins. Invest Ophthalmol Vis Sci 30:731-8
Rosenquist, R; Epstein, D; Melamed, S et al. (1989) Outflow resistance of enucleated human eyes at two different perfusion pressures and different extents of trabeculotomy. Curr Eye Res 8:1233-40
Johnson, M; Ethier, C R; Kamm, R D et al. (1986) The flow of aqueous humor through micro-porous filters. Invest Ophthalmol Vis Sci 27:92-7