Abstract
Purpose: :
Heat shock protiens(HSPs) are present in rat retina, and have been implicated in neuronal protection. We determine whether retinal cells under oxidative stress induce HSPs to protect the retinal cells. Glutathione(GSH) plays a critical role in the cellular defense against oxidative stress in mammalian cells, so we induced the oxidative stress by depletion of GSH in the retinal cells.
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 immunohistochemical analysis using anti–HSP antibodies.
Results: :
After 1 day of treatment with BSO, we observed the significant induction of HSP70 in cells in the retina. In particular, large cell bodies in the ganglion cell layer were highly positive. We also observed similar induction of HSP25. The induction of HSPs was maintained upto 2, 4, and 7 days in the retina.
Conclusions: :
Under the experimental conditions used, retinal cells induced HSP27 and HSP70 under GSH depletion. Thus, HSPs may provide cellular protection in retinal cells against oxidative stress, which in turn prevents retinal cells from neuronal damages.
Keywords: oxidation/oxidative or free radical damage • neuroprotection • retina