Experimental Glaucoma After Oxidative Stress and Modulation of the Consequent Apoptotic Events in a Rat Model

Glaucoma derives from an increase of the intra-ocular pressure (IOP) due to accumulation of the aqueous humor which causes degenerative events at the level of the retina and the optic nerve. This results in a progressive damage of the optic nerve that is paralleled by the gradual loss of retinal ganglion cells (RGC). The pathology causes increasing eyesight deterioration particularly in the peripheral areas of the visual field. The optic nerve papilla becomes paler and shows an augmented excavation as compared with a normal physiological situation. The increase of the IOP is to be ascribed, in the majority of cases, to an alteration of the ocular hydrodynamics: in particular the normal efflux of aqueous humor from the anterior chamber of the eye is severely hindered. The drainage system is located in the limbal regions or in the sclero-corneal junction. The inner surface presents a hollow (depression) known as inner scleral spur which is filled by the trabecular meshwork and the canal of Schlemm. Primary open angle glaucoma is caused by the failure of drainage from the trabecular meshwork, while the primary closed angle glaucoma consists in a modification of the iris-corneal angle. It is commonly accepted that glaucoma is the second cause of blindness in the world; as a matter of fact it has been estimated that 68 millions of patients are affected by this pathology and out of them, about 7 millions suffer complete bilateral blindness as a consequence of the glaucoma. The onset of the disease may occur at any age, also at childhood, but it is significantly more frequent in elderly people. Glaucoma is generally categorized in five different groups; two of them are the above mentioned open and closed angle primary glaucoma which are also the most widespread ones. A broad variety of pathological conditions may induce, as secondary