Abstract | PURPOSE: Low concentrations of excitotoxic agents such as glutamate decrease survival of retinal ganglion cells (RGCs) and may be an important cause of RGC death in a variety of retinal diseases. Arachidonic acid (AA), an intercellular messenger in the central nervous system, has been reported to have multiple effects on glutamate receptors, including an inhibitory effect on non- N-methyl-D-aspartate ( NMDA) receptors. The purpose of this study was to test the hypothesis that AA could protect RGCs from glutamate neurotoxicity. METHODS: RGCs were purified from the rat retina on postnatal days 7 and 8 by a modified two-step panning method. Survival of RGCs after exposure to glutamate, with or without AA treatment, was measured after 3 days in culture. To visualize calcium signals, RGCs were loaded with a calcium indicator dye, fluo-3 acetoxymethyl ester, and the fluorescence was measured by laser scanning confocal microscopy. Electrophysiological effects of AA on non- NMDA ionotropic receptors were examined by using whole-cell patch clamp configurations. RESULTS: CONCLUSIONS: Low concentrations of AA can reduce glutamate neurotoxicity to RGCs by the inhibition of non- NMDA ionotropic receptors. These results suggest that endogenous or exogenous AA may be used to protect RGCs from glutamate neurotoxicity and that AA may be one potential treatment for RGC loss in a variety of eye diseases, including glaucoma.
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Authors | Atsushi Kawasaki, Ming-Hu Han, Ji-Ye Wei, Keiji Hirata, Yasumasa Otori, Colin J Barnstable |
Journal | Investigative ophthalmology & visual science
(Invest Ophthalmol Vis Sci)
Vol. 43
Issue 6
Pg. 1835-42
(Jun 2002)
ISSN: 0146-0404 [Print] United States |
PMID | 12036987
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, P.H.S.)
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Chemical References |
- Aniline Compounds
- Fluorescent Dyes
- Neuroprotective Agents
- Receptors, N-Methyl-D-Aspartate
- Xanthenes
- Fluo-3
- Arachidonic Acid
- Glutamic Acid
- Calcium
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Topics |
- Aniline Compounds
(metabolism)
- Animals
- Animals, Newborn
- Arachidonic Acid
(pharmacology)
- Calcium
(metabolism)
- Cell Survival
(drug effects)
- Cells, Cultured
- Cytoprotection
- Dose-Response Relationship, Drug
- Electrophysiology
- Fluorescent Dyes
(metabolism)
- Glutamic Acid
(toxicity)
- Microscopy, Confocal
- Neuroprotective Agents
(pharmacology)
- Patch-Clamp Techniques
- Rats
- Rats, Long-Evans
- Receptors, N-Methyl-D-Aspartate
(antagonists & inhibitors)
- Retinal Ganglion Cells
(drug effects, metabolism)
- Xanthenes
(metabolism)
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