Experience triggered by enriched environment protects visual pathway alterations induced by experimental glaucoma in adult rats

GONZÁLEZ FLEITAS, MARÍA F; ARANDA, MARCOS L; DORFMAN, DAMIÁN; MILNE, GEORGIA A; DEVOUASSOUX, JULIÁN D; DIEGUEZ, HERNÁN H; CHIANELLI, MÓNICA S; KELLER SARMIENTO, MARÍA I; SANDE PABLO H; ROSENSTEIN, RUTH E

Buenos Aires

Congreso; Reunión Conjuntas de Sociedades Biomédicas, LVIII Reunión Anual de la Sociedad Argentina de Investigación Clínica; 2017

Glaucoma is a leading cause of blindness, characterized by retinal ganglion cell (RGC) loss and optic nerve damage. Increased intraocular pressure (IOP) is the most accepted risk factor for developing glaucomatous neuropathy, however many patients with successful IOP control continue to lose vision. Enriched environment (EE) is a paradigm that involves sensory, cognitive, motor, and social stimulation. The aim of this work was to analyze whether the exposure to EE prevents glaucomatous alterations. Adult male Wistar rats received 30% hyaluronic acid (Z-HYALCOAT®) in the anterior chamber of one eye and vehicle in the contralateral eye, once a week, and were housed in standard environment (SE) or EE for 10 weeks. Animals were subjected to functional (electroretinogram (ERG) and flash visual evoked potentials (VEPs) recording with skull-implanted electrodes), and histological analysis. The number of RGCs was assessed by Brn3a-immunoreactivity. An immunohistochemical analysis of Iba1 (microglia and macrophage marker), and glial fibrillary acidic protein (GFAP) levels in the retina and optic nerve was performed. EE housing which did not affect IOP (p<0.05), prevented the decrease in VEP (p<0.05) and oscillatory potential amplitude (p<0.05), as well as the increase in Iba1- (p<0.05) and GFAP-immunoreativity (p<0.05) in the retina and optic nerve. Moreover, EE exposure preserved RGC number in the central (p<0.05) and peripheral retina (p<0.01). These results suggest that the EE housing protects the visual pathway against damage induced by experimental glaucoma in adult rats.