OBJECTIVE: To observe the effect of recombinant human erythropoietin (rhEPO) on the expression of hypoxia inducible factor-1alpha (HIF-1alpha) in the retina of rabbits with acute high intraocular pressure and investigate the mechanism of rhEPO in protecting the retina from ischemia-reperfusion injury. METHODS: Acute high intraocular pressure was induced in the rabbits by perfusion of normal saline into the anterior chamber, and rhEPO was injected subcutaneously. The changes in HIF-1alpha protein expression in the retina was observed by immunohistochemistry on days 1, 3, 7, and 14 after retinal ischemia- reperfusion. RESULTS: HIF-1alpha expression was not observed in the retina of the normal control rats, but intense HIF-1alpha expression was found in the model group (P<0.01). In rabbits with rhEPO injection and those in the model group, the patterns of HIF-1alpha expression alterations were similar, but the HIF-1alpha-positive cells in the retina were significantly fewer in rhEPO group (P<0.05). CONCLUSION: rhEPO can down-regulate HIF-1alpha expression in the retina of rabbits with acute high intraocular pressure, which may be one of the mechanisms that rhEPO protects the retina from ischemia-reperfusion injury.
OBJECTIVE: To observe the effect of recombinant humanerythropoietin (rhEPO) on the expression of hypoxia inducible factor-1alpha (HIF-1alpha) in the retina of rabbits with acute high intraocular pressure and investigate the mechanism of rhEPO in protecting the retina from ischemia-reperfusion injury. METHODS: Acute high intraocular pressure was induced in the rabbits by perfusion of normal saline into the anterior chamber, and rhEPO was injected subcutaneously. The changes in HIF-1alpha protein expression in the retina was observed by immunohistochemistry on days 1, 3, 7, and 14 after retinal ischemia- reperfusion. RESULTS:HIF-1alpha expression was not observed in the retina of the normal control rats, but intense HIF-1alpha expression was found in the model group (P<0.01). In rabbits with rhEPO injection and those in the model group, the patterns of HIF-1alpha expression alterations were similar, but the HIF-1alpha-positive cells in the retina were significantly fewer in rhEPO group (P<0.05). CONCLUSION: rhEPO can down-regulate HIF-1alpha expression in the retina of rabbits with acute high intraocular pressure, which may be one of the mechanisms that rhEPO protects the retina from ischemia-reperfusion injury.