幼年大鼠LED光源性近视模型的建立OA

Objective To establish and evaluate a rat model of myopia induced by light-emitting diode(LED)light exposure.Methods Forty 3-week-old male SPF rats were randomly divided into control and model groups(n=20).Axial length was measured before the experiment and at weeks 2,4,and 6.Scleral morphological changes were observed using hematoxylin and eosin(HE)staining.Serum melatonin concentration was measured by enzyme-linked immunosorbent assay.Western Blot was applied to determine matrix metalloproteinase-2(MMP-2)and tissue inhibitor of metalloproteinases-2(TIMP-2)protein expression in retinal tissue,and RT-qPCR was used to detect their messenger RNA(mRNA)expression in scleral tissue.Results The model group showed significantly elongated axial lengths at weeks 4 and 6 compared with the control group(P＜0.05).Scleral tissue exhibited disorganized and sparse collagen fibers,scleral layer thinning,and a significantly reduced serum melatonin concentration(P＜0.05).In addition,MMP-2 protein expression in retinal tissue and mRNA expression in scleral tissue were significantly upregulated,while TIMP-2 expression was significantly downregulated(P＜0.05).Conclusions Long-term LED light exposure can induce axial elongation,destroy scleral structural integrity,and regulate scleral MMP-2/TIMP-2 signaling,successfully establishing a rat model of LED light-induced myopia.