Retinopathy of prematurity in a model of perinatal asphyxia : effects of cold treatment.

REY-FUNES, M; CAPANI, F; LOPEZ, E ; LOPEZ-COSTA, J. ; CRAVEDI, V. ; PELAYES, D. ; ZARATE, J. ; LOIDL, F.1 ; COIRINI, H.

Congreso; Meeting of the American Society for Neuroscience; 2003

Perinatal asphyxia (PA) is a transient global ischemia that may induce behavioral deficits and neuropathological damage being the retinopathy of prematurity one of the most important. The objective of this study was to test if an experimental model of global PA might be used to study the morphological alterations of this disease. We also studied the protective effects of hypothermia. Pregnant rats uteri still containing fetuses were taken out and PA was induced by immersion in a water bath at 37°C during 19 min and 20 min. Hypothermia was induced in a water bath at 15 °C. After 2 months animals were sacrificed by decapitation, eyes taken out and fixed by immersion in paraformaldehyde 4 % overnight. We processed retinas for hematoxilin and eosin (H+E) staining and for immunocytochemistry for Glial Fibrillary Acidic Protein (GFAP). We observed with H+E staining, neovascularization in the inner areas of the retina after 19 and 20 min of PA compatible with vitreoretinal neovascular membrane described in clinic conditions in humans. Increment in the GFAP immunoreactivity was seen in the inner limiting membrane consistent with the localization of the epiretinal fibrous membrane in human retinopathy. We did not observed neovaslurization and the epiretinal fibrousus membrane was thinner after hypothermia treatment. These results show that this experimental model of PA is applicable for studying the pathological mechanisms involved in the retinopathy of prematurity and vitreiretinal interfaces disease. Moreover hypothermia is an excellent therapeutic tool to reduce the retinal damage. Supported by Supported by UBACYT # M047