Primary open angle glaucoma is almost certainly a result of changes in the metabolism of trabecular meshwork (TM). This was recognized by the Glaucoma Panel in its 1983 report to the National Advisory Eye Council when it stated as an objective """"""""To define the biology and pharmacology of the aqueous humor outflow pathways at the cellular, tissue, and organ levels -----"""""""". This proposal is centered in this set of objectives. The pathogenetic mechanism of glaucoma is still unknown. However, we will take as our working hypothesis that glaucoma is the result of failure to cope with chronic exposure to oxidative insult, in particular the hydrogen peroxide present in human aqueous humor. Even if wrong, the focused effort will produce a coherent body of useful information on the biology of TM. The use of excised calf TM as a model system will continue to be the mainstay of our work. An important new development is our ability to produce isolated cell suspensions of calf TM. Experience with other tissues has shown that there are great advantages in such a preparation. The difficulty of working with excised human TM and the uncertainty of the supply necessitate a new approach. We propose to develop methods for perfusing preparations of isolated TM mounted on corneoscleral buttons, four from each eye. The enzymes of energy metabolism, etc. will continue to be studied, but the primary emphasis has shifted to enzymes participating in the defense of TM against oxidative damage. Potential targets of oxidative damage will also be studied, such as the membrane ATPases, hormone receptors, and membrane lipid. An attempt will be made to develop an oxidative damage model of glaucoma in rabbits by manipulations designed to raise aqueous H2O2 levels.

Agency
National Institute of Health (NIH)
Institute
National Eye Institute (NEI)
Type
Research Project (R01)
Project #
5R01EY003921-09
Application #
3258395
Study Section
Visual Sciences A Study Section (VISA)
Project Start
1981-09-01
Project End
1991-08-31
Budget Start
1989-09-01
Budget End
1990-08-31
Support Year
9
Fiscal Year
1989
Total Cost
Indirect Cost
Name
Massachusetts Eye and Ear Infirmary
Department
Type
DUNS #
073825945
City
Boston
State
MA
Country
United States
Zip Code
02114
Nguyen, K P; Chung, M L; Anderson, P J et al. (1988) Hydrogen peroxide removal by the calf aqueous outflow pathway. Invest Ophthalmol Vis Sci 29:976-81
Lee, D A; Flores, R A; Anderson, P J et al. (1987) Glaucoma filtration surgery in rabbits using bioerodible polymers and 5-fluorouracil. Ophthalmology 94:1523-30
Nguyen, K; Lee, D A; Anderson, P J et al. (1986) Glucose 6-phosphate dehydrogenase of calf trabecular meshwork. Invest Ophthalmol Vis Sci 27:992-7
Nguyen, K P; Weiss, H; Karageuzian, L N et al. (1985) Glutathione reductase of calf trabecular meshwork. Invest Ophthalmol Vis Sci 26:887-90
Freedman, S F; Anderson, P J; Epstein, D L (1985) Superoxide dismutase and catalase of calf trabecular meshwork. Invest Ophthalmol Vis Sci 26:1330-5