Abstract:AIM:To explore regulative effect of recombinant human erthropoietin(rhEPO) on the expressin of Bcl-2 and Bax protein on retina following eye contusion, and to clear the protective mechanism of rhEPO for traumaic retina. METHODS: Of 45 two-month old male SD rats, 5 rats were obtained at random for normal control group.The left eye contusions were made by modified Allens falling strike for the rest 40 rats.Successful model rats were randomly divided into model group and rhEPO group. Each group is subdivided into 4 groups according to the different time point (12,24 hours,3,7 days), 5 rats per group.The rhEPO group animals were injected with rhEPO intraperitoneally,once a day. The model group animals were injected with physiological saline.The retina specimen were gotten after stopping giving rhEPO and physiological saline. Paraffin retinas sections were made and the expressions of Bcl-2 and Bax protein in the rat retinas were tested with immunohistochemistry staining. RESULTS: The expressions of Bcl-2 and Bax protein were modest in normal groups. With prolonging of time, The expression of Bcl-2 protein decreased gradually, and reached minimum at 3 days after ocular trauma in normal groups. Except for 12 hours, the expression of Bcl-2 protein was lower in model groups than that in normal groups at each time point, while the expression of Bax protein gradually increased and reached peak at 3 days after ocular trauma in model group. Except for 12 hours, the expression of Bax protein was higher in model groups than that in normal groups. The expression of Bcl-2 protein was obviously higher in rhEPO groups than that in model groups, while the expression of Bax protein was obviously higher in rhEPO groups than that in model groups at 24 hours, 3 days and 7 days. CONCLUSION:Bcl-2 and Bax take part in pathologic process of ocular trauma; rhEPO upregulates the expression of Bcl-2 and downregulates the exprssion of Bax on retina cells following ocular trauma, which maybe inhibits the apoptosis of retina cells.