To investigate the effect of transient ischemia reperfusion on the retina in rats Methods Retinal ischemia reperfusion was induced in rats by increasing the intraocular pressure After 1 or 5 minutes of ischemia, retinal neuronal cell death at diffesent periods of reperfusion was studied using the TdT deoxynucleotide terminal nick end labeling (TUNEL) method and light microscopy Retinal IL 1β and TNFα were quantified by an enzyme linked immunosorbent assay (ELISA) Results A few migrating leukocytes were noticed in the retina after transient retinal ischemia reperfusion Rare TUNEL positive (T+) cells were noticed in the outer granular layer or the rod and cone layer, and not in ganglion cell layer in control eyes, but they were significantly increased in the outer granular layer, the inner granular layer, and ganglion cell layer in the eyes treated with 1 or 5 minutes of retinal ischemia reperfusion ( P <0 05) Retinal IL 1β was significantly increased at 6 hours after reperfusion in the eyes treated with 1 or 5 minutes ischemia over the control eyes ( P <0 05), but retinal TNFα was not significantly increased ( P >0 05 ) Conclusion Transient retinal ischemia reperfusion for only 1 or 5 minutes of ischemia can induce the upregulation of retinal IL 1β and apoptosis of retinal neuronal cells This kind of apoptosis in individual cells, however, was not sufficient to affect the whole retinal function To investigate the effect of transient ischemia reperfusion on the retina in rats Methods Retinal ischemia reperfusion was induced in rats by increasing the intraocular pressure After 1 or 5 minutes of ischemia, retinal neuronal cell death at diffesent periods of reperfusion was studied using the TdT deoxynucleotide terminal nick end labeling (TUNEL) method and light microscopy Retinal IL 1β and TNFα were quantified by an enzyme linked immunosorbent assay (ELISA) Results A few migrating leukocytes were noticed in the retina after transient retinal ischemia reperfusion Rare TUNEL positive (T +) cells were noticed in the outer granular layer or the rod and cone layer, and not in ganglion cell layer in control eyes, but but were significantly increased in the outer granular layer, the inner granular layer, and ganglion cell layer in the eyes treated with 1 or 5 minutes of retinal ischemia reperfusion (P <0 05) Retinal IL 1β was si gnificantly increased at 6 hours after reperfusion in the eyes treated with 1 or 5 minutes ischemia over the control eyes (P <0 05), but retinal TNFα was not significantly increased (P> 0.05) Conclusion Transient retinal ischemia reperfusion for only 1 or 5 minutes of ischemia can induce the upregulation of retinal IL 1β and apoptosis of retinal neuronal cells This kind of apoptosis in individual cells, however, was not sufficient to affect the whole retinal function