Neuroprotective Effect of the Recombinant Human Erythropoietin in the Enthorinal Cortex and Thalamus of Rats Exposed to Focal Cerebral Ischemia

Abstract

Objective: Neuroprotective potential of recombinant human erythropoietin (rhEpo) was reported in various experimental models of brain damage but the exact mechanism of its effect is still unclear. In the present study, the effect of rhEpo administration on the level of neuronal loss and neurodegenerative changes in the dorsolateral band of the entorhinal cortex and ventral posteriomedial nucleus of the thalamus in rats following focal cerebral ischemia was examined.Methods: Focal cerebral ischemia was induced in male Hanover Wistar rats (250-350 g) by right middle cerebral artery occlusion (MCAO) model for 1 h. After 23 h of reperfusion, ischemic animals were sacrificed and the neuronal damage was detected using the Fluoro Jade B fluorescent staining to detect neurodegeneration, together with NeuN immunostaining used to detect neuronal loss. Ischemic animals received either vehicle or rhEpo (5000 IU/kg, intraperitoneally) 3 hrs after MCAO, and were sacrificed 21 h later. Sham operated; vehicle treated animals served as the control group.Results: Administration of rhEpo significantly increased the NeuN immunoreactivity in the entorhinal cortex compared to the neuronal loss detected in ischemic, non-treated animals and decreased the number of Fluoro Jade B positive neurons in comparison to neuronal damage detected in ischemic, nontreated animals. The effect of rhEpo treatment in thalamus was not significant.