AIM:To explore the relationship between the expression of Fas/FasL and the cell apoptosis in retinal ischemia reperfusion(IR)injury of rats,as well as the therapeutic effects of α-lipoic acid in the ischemic retina.METHODS:The models of retinal IR injury were made by transient elevating intraocular pressure.A total of 54 rats were divided into normal group,IR injury group and α-lipoic acid treatment group.The latter two groups were subdivided into 12,24,48 and 72 hours groups.The number of retinal ganglion cells and the thickness of the inner retinal layers were detected by HE staining method.Apoptosis was assessed by the terminal deoxynucleotidyl transferase mediated dUTP nick end labelling method,and the expression of Fas/FasL was studied by immunohistochemistry.RESULTS:The thickness of the inner retinal layers thinned and the number of retinal ganglion cells decreased in IR injury group.There was a significant number of TUNEL positive cells 12 hours after transient ischemia followed by a decrease at the 48 hour.The expression of Fas and FasL was in coincidence with apoptosis.In treatment group,the thickness of the inner retinal layers and the number of retinal ganglion cells reduced.Apoptosis of retina and expression of Fas and FasL were obviously lower than that in IR injury group(P<0.05).CONCLUSION:α-lipoic acid can rescue retinal IR injury through downregulation of the expression of Fas/FasL.