| Diabetic retinopathy (DR) is one of serious microvascular complications in diabetesmellitus (DM). The pathological characteristic of proh'ferative diabetic retinopathy(PDR) are neovascularization and fibrosis, which induce retinal detachment, and become the main reason resulting in blindness. Therefore, pathogenesis, prevention and cure have become the hot spot of research at present in the world. The main characteristic of DR is neovascularization, and growth factors play the important role in accelerating neovascularization. Basic fibroblast growth factor (bFGF) can stimulate proliferation of retinal endothelial cells, for which bFGF is a potent mitogen. bFGF also regulate metabolism of extracellular matrix, accelerate degradation of collagen .So bFG can play very important role in neovascularization during the whole process of neovascularization. bFGF plays the important role at early stage of diabetic retinopathy before vascular endothelial growth factor (VEGF) does. bFGF not only has the synergistic action with VEGF, but also induce VEGF expression of endothelial cells. The target organs of bFGF are retinalendothelial cells, pigment epithelial cells, pericytes, Mtiller cells. Muller cell is chief component retinal glial cells spanning the entire width of the retina, and extending their apical microvilli into the interphotreceptor matrix. Muller cells act as supporting and nutrition of retina, and maintenance of retinal integrity, which are known to respond to pathological factors. Onset of DR is supposed to a complex pathological process. Continuing high glucose maybe prerequisite, initiation agent either, in DM. It is positive correlation between glucose level and DR. In order to know the change of bFGF in DR, we used diabetic rabbit models to investigate bFGF expression and immunocytochemical location in retina. Experiment also focused on rabbit retinal Muller cells, to investigate the mechanism of bFGF expression of Muller cells under high glucose condition. Our study provided the theoretical basis for postponing and amelioration of DR with inhibiting the new blood vessels formation. And it may be benefit to prevent and cure DR, decrease incidence rate of DR, raise the quality of patients life.I. There is bFGF expression in diabetic animal model without obvious change of retinal morphology, which confirm the role bFGF playing at the early stage of diabetic retinopathy. The immunochemistry with double fluorescent labeling was employed, dual wavelength laser-scanning confbcal microscopy was carried our to investigate the immunocytochemistry location of bFGF. The results showed bFGF and GFAP co-express in the same cell, which suggested that Muller cells secrete bFGF at the early stage of DM.II. The experimental model of primary culture of rabbit retinal Muller cells was established to study on the cells with elimination ofagents in vivo. Stereomicroscope , suitable medium and subculture was utilized to obtain pure Mailer cells. Deficiency of specific antibody for Muller cells, it is necessary to depend on associated evaluation. Electron microscopy, immunocytochemical method with antibody GFAP, S-100, factor VI related antigen, PAS staining, and GFAP immunofluorescence were used to confirm that the cells obtained with suspended constitution were Muller cells. The purity is about 95 percent.III. To observe the effect of 50mM glucose on bFGF expression of Muller cells, we used immunochemistry and RT-PCR methods. The immunochemical results were that bFGF expression was enhanced obviously by the regulation of high glucose compared with die control group(P<0.01). Culturing Muller cells 3 days with 50mM glucose enhanced bFGF mRNA expression obviously compared with the control group (P<0.01). Calphostin C is the specific inhibitor of PKC, and 50mM glucose + 50nm calphostin C can decrease bFGF mRNA expression significantly compared with the control group (P<0.01). The results showed that high glucose enhanced bFGF mRNA expression through activation PKC pathway. Inhibiting activation of PKC...
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