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Abstract #19421 Published in IGR 9-3
The protective function of erythropoietin to the rat retina after acute intraocular hypertension
Guo Y; Wang W-HInternational Journal of Ophthalmology 2007; 7: 688-691
AIM: To investigate the protective function and mechanism of recombinant human erythropoietin (rhEPO) pretreatment on the rat retina with acute intraocular hypertension injury. METHODS: Thirty-six healthy male Wistar rats were randomly divided into 3 groups: normal group (n = 4, killed directly without any treatment), saline group (n = 16, physiological saline was administered i.p. 3 hours before raising intraocular pressure [IOP]), rhEPO group (n = 16, rhEPO was administered i.p. 3 hours before raising IOP). Either of bilateral eyes was randomly made into the acute high IOP model using the method of saline perfusion into anterior chamber until the IOP reached 100 mmHg, then sustained the IOP for 60 minutes. All the rats were killed respectively and the eyeballs were enucleated at different observation periods after the model was successfully established (6, 24, 48 and 72 hour). The histological changes of retina were observed by HE staining; the expression and distribution of apoptotic cells and p-Akt protein were observed respectively by using TUNEL detection and immunohistochemistry. The data was statistically analyzed. RESULTS: 1 The acute high IOP damaged the rat retina, the inner layer of retina got thinner and its percentage of whole retina was decreasing in the saline group, but the percentage of the rhEPO group was bigger than that of the saline group, the difference was significant (P < 0.01); 2 No TUNEL-positive cells were seen in the normal group, the apoptotic cells of the other two groups were observed in the retinal ganglion cell layer (RGL) and inner nuclear layer (INL). There were less apoptotic cells in the rhEPO group than those in the saline group, the difference was significant (P < 0.01); 3 The minute expression of p-Akt protein was found in the normal group, while the p-Akt positive cells which were expressed in the RGL, inner plexiform layer (IPL) and INL were observed both in the saline group and the rhEPO group. There were stronger expression in the rhEPO group than those in the saline group, the difference was of significance (P < 0.01). The expression of p-Akt in RGL and INL is stronger than that in IPL. CONCLUSION: The damage caused by the acute intraocular hypertension was mainly occurred in RGL, IPL and INL, while rhEPO pretreatment can lessen the damage and the cell apoptosis. The mechanism of rhEPO's protective function may be the activation of PI3K/Akt signaling pathway and up regulation p-Akt in retina, which can restrain cell apoptosis. LA: Chinese
Dr. W.-H. Wang, Department of Ophthalmology, Second Hospital of Shanxi Medical University, Taiyuan 030001 Shanxi Province, China. wangwhui@public.ty.sx.cn
Classification:
11.14 Investigational drugs; pharmacological experiments (Part of: 11 Medical treatment)
5.1 Rodent (Part of: 5 Experimental glaucoma; animal models)
