| Corneal neovascularization is a pathologic process which involves the interplay of a large of regulatory and growth factors. In 1975, Fromer and Klintworth demonstrated that polymorphonuclear leukocyte infiltration leaded to corneal vascular proliferation, and the relationship between PMNL inf ltr*tion and corneal neovascularization was a cause-and-effect. The infiltrated leukocytes are suspected to secrete angiogenic and chemotactic factors, including bFGF , VEGF and prostaglandins. The peptide growth factors induce endothelial cell proliferation, migration, and chemotaxis to involve the formation of new blood vessels. Among these factors, bFGF and VEGF are the most potent angiogenesis inducers, and occasionally applied to induce corneal neovascularization. It has been proved that both bFGF and VEGF involve the regulation of inflammatory corneal neovascularization. However, it is not fully understood that the mechanisms of these angiogenic factors regulating alkali cauterization-induced neovascularization in the rat cornea, including when and at which localization they exert their angiogemic activity in alkali-burned rat corneas.In the present studies, inflammatory corneal neovascularization was induced by cauterization with Imol/L sodium hydroxide in the rat corneas. At the different time points after corneal cauterization with alkali, bFGF and VEGF proteins was investigated by Coomassie brilliant blue dye and Western blot analysis. To localize VEGF and bFGFprotein in the epithelium and stroma of the cauterized rabbit corneas, paraformaldehyde-6fixed and paraffin-embedded histological cross sections of corneas were examined by immunohistochemistriy. Amniotic membrane can facilitate corneal epithelization and have the effects of antiangiogenisis and.antiinflammation. Amniotic membrane transplantation has been reported to be effective surgical procedure for the ocular surface diseases. In present studies, inflammatory corneal neovascularization was induced by cauterization with Imol/L sodium hydroxide in rabbit corneas. Amniotic membrane transplantation (AMI) was performed on rabbit corneas with alkali burns to compare the therapeutic effects of preserved human amniotic membrane transplantation (AMT) for treating corneal neovascularization following rabbit corneal alkali burns with those of fresh human amniotic membrane transplantation (F-AMT) , and to determine the surgical timing of preserved amniotic membrane transplantation for treating corneal neovascularization following the rabbit corneal alkali burns.PARTIStudy on Mechanisms of Vascular Endothelial Growth Factor and Basic Fibroblast Growth Factor Inducing Neova.scularization in Rat Corneal Burns with Alkali ( I )Objective: Corneal neovasculari/ation following cauterization with alkali is a complex pathological process, which is involved by numerous factors. This part is designed to investigate the expression of the most potent angiogenesis inducers, vascular endothelial growth factor and basic fibroblast growth factor, in the rat corneas after cauterization with alkali. To explore the mechanisms of vascular endothelial growth factor and basic fibroblast growth factor inducing corneal neovascularization.Methods:1. Animal preparation: In Sparague-Dawley (SD) rats, 36 healthy SD rats were selected randomly. They were divided into six groups according to the time after alkali burns (0, 6, 24, 48, 96, 168h ). Inflammatory corneal neovascularization was induced bycauterization with Imol/L sodium hydroxide.2. After rats were sacrificed, six eyes of six rats were removed at each of six time points-(K 6^ 24> 48^ 96> 168h after corneal cauterization with alkali-and used for sample preparation (total 36 rats). Protein concentrations were measured by the Lowry method. Equal amounts of protein from each sample were used for SDS-PAGE. The desired proteins ware showed by Coomassie brilliant blue dye and western blot analysis, respectively. The absorbed light value of immune signals were measured and statistically analyzed.
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