To explore the effect of hydrogen sulfide(H₂S) on cell apoptosis and expression of Bcl-2/Bax in rat retinal ischemia-reperfusioninjury(RIRI). METHODS:A total of 54 SD rats were randomly divided into normal control group,ischemia-reperfusion model group and sodium hydrosulfide(NaHS) treatment group,the last two groups were subdivided into group 6, 24, 48, 72 hours after reperfusion. The models of RIRI were made by elevating intraocular pressure.Apoptosis was assessed by the terminal deoxynucleoitidyl transferase mediated dUTP nick end labeling method,and the expression of Bcl-2/Bax was studied by immunohistochemistry. RESULTS:There was a significant number of TUNEL positive cells 6 hours after transient ischemia peaked at the 24 hours, followed by a decrease at the 48 hours. Compared with RIRI group, Bcl-2 protein expression was increased, Bax protein level were decreased in NaHS group (all P<0.05). CONCLUSION: H₂S can enhance the expression of Bcl-2,decrease the expression of Bax, increase the Bcl-2 /Bax ratio and decrease the apoptosis of ganglion cells. H₂S shows a significant protection for retinal ganglion cells with RIRI.