Abstract
Purpose: :
Oxidative stress affacts all intracellular macromolecules, and leads cells including neurons to death. Glutathione(GSH) is known to play a critical role in the cellular defense against oxidative stress in mammalian cells. So, we determine whether glutathione depletion induces oxidative stress in cells of retina, and in turn leads to apoptosis.
Methods: :
Rats were intraperioneally injected with buthionine sulphoximine(BSO) at 1.5g/kg. For controls, rats were injected with phosphate buffered saline (PBS pH 7.4). Three animals were used for each condition. After 1, 2, 4, and 7 days of injection, the animals were killed under anesthesia and the retina sections were prepared at 10 micrometer. The retinal sections were subjected to terminal uridine deoxynucleotidyl nick end labelling(TUNEL) analysis. TUNEL–positive cells were counted at 20X magnification. 10 sections for each animal were counted.
Results: :
After 1 day of treatment with BSO, we observed the significant increase in TUNEL positive cells in the retina. In particular, large cell bodies in the ganglion cell layer were highly positive. However, post 2,4, and 7 days of injection, we failed to observe such changes in TUNEL positive cells in the retina.
Conclusions: :
Under the experimental conditions used, glutathione depletion indeed increased cell death in the retina. Thus, glutathione may provide cellular protection in cells in the retina against oxidative stress, which in turn prevents retinal cells from neuronal degeneration.
Keywords: apoptosis/cell death • oxidation/oxidative or free radical damage • retina