Interferential Effect Of Erythropoietin On Apoptosis Of Retinal Cell In Experimental Retinal Detachment

Objective:To study whether erythropoietin(EPO)have the ability to protect retinal cell or not in this experiment retinal detachment(RD).Methods:Choose 48 healthy Sprague-Dawley(SD)rats of 200-300g.They were divided into 3 group:normal control group, erythropoietin(EPO)treated group and normal saline(NS)control group.Both EPO treated group and NS control group had 20 rats and normal control group had 4 respectively.EPO treated group and NS control group were used as an RD animal model by injection of sodium hyaluronate under the neurosensory retina.EPO(5000IU/kg)or isodose NS was injected into peritoneal cavity 4 hours before experiment models of RD was induced in both eyes of each rat.The rats were sacrificed at 1, 6,12,24,72h after RD.The morphologic changes of retina were observed by light microscope.The terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling(TUNEL)technique was applied to assess the retinal apoptosis.The apoptotic cells in the groups were measured and analyzed by statistics.Results:1.Light examination:Normal retinal layers were clear.And the retina had regular structure. 2.At 1h after RD,the edema of retina was obvious by light microscope.In the 72h after RD,EPO treated group and NS control group had damaged layers:ganglion cells,inner nuclear layer cells and outer layer cells decrease,and inner and outer segment impairment.EPO treated group had a slighter damaged inner and outer segment,more retinal cells,more regular retinal structure than those in the NS control group.3.TUNEL staining indicated:Normal rat retina had almost no positive apoptotic cell.The apoptotic cells of retinal ganglion cells and inner nuclear layer cells in 1,12,24,72h,EPO treated group were less than NS control group,which had a significant difference(P＜0.05).The apoptotic cells of retinal outer nuclear layer cells in12,24,72h,EPO treated group were less than NS control group,which had a significant difference(P＜0.05).Conclusion:In the 72h after retinal detachment,the retina of rats had changed significantly.And apoptotic cells in retinal layers were observed,which increased all the time.EPO treat group had less apoptotic cells than those in the NS control group.So,EPO protect retinal cell from apoptosis in experimental retinal detachment.