Objective:To observe the effect of Nodal on the biological behavior of retinal vascular endothelial cells (RF/6A cells) in monkeys with high glucose.Methods:RF/6A cells were divided into normal group, mannitol group, high glucose group, high glucose combined with non-specific small interfering RNA treatment group (HG+NC group), high glucose combined with small interfering Nodal treatment group (HG+siNodal group). The transfection efficiency of siNodal was observed by real-time fluorescence quantitative PCR and western blot protein immunoblotting. The effect of Nodal on the proliferation of RF/6A cells was detected by thiazole blue colorimetry. The effect of Nodal on migration ability of RF/6A cells was detected by cell scratch assay. The effect of Nodal on the formation of RF/6A cell lumen was measured by Matrigel three-dimensional in vitro. The expression of extracellular signal phosphorylated regulated kinase 1/2 (pERK1/2) in RF/6A cells was detected by western blot protein immunoblotting. One-way analysis of variance was used to compare groups.Results:Compared with HG+NC group, Nodal protein ( F=33.469) and mRNA relative expression levels ( F=38.191) in HG+siNodal group were significantly decreased, cell proliferation was significantly decreased ( F=28.548), and cell migration ability was significantly decreased ( F=24.182). The number of cell lumen formation was significantly decreased ( F=52.643), and the differences were statistically significant ( P<0.05). Compared with HG+NC group, the relative expression of pERK1/2 protein in HG+siNodal group was significantly decreased, and the difference was statistically significant ( F=44.462, P<0.01). Conclusions:Silencing Nodal expression can inhibit proliferation, migration and tube formation of RF/6A cells induced by high glucose. It may act by inhibiting pERK1/2 expression.