Abstract: Objective: To study the effect of insulin on angiogenesis in RF/6A retinal vascular endothelial cells and elucidate the underlying mechanism. Methods : RF/6A cells were treated with 01nmol/L、 1nmol/L and 100 nmol/L of insulin respectively and MTS, cells migration experiment and lumen formation experiment were used to test cell proliferation, migration and lumen formation respectively,.RT-PCR and Western bot were used to measure the expression of vascular endothelial growth factor receptors VEGFR and phosphorylated receptors . Results : Insulin promoted RF /6A cell proliferation, migration and lumen formation (all P<0.01). Insulin also increased the both the expression of VEGFR2 mRNA and its phosphorylation (P< 0.01or P<0.05). There was no significant difference in the expression of VEGFR1 mRNA among the groups (P> 0.05). Conclusion Insulin might promote RF/6A angiogenesis via a VEGFR2 mediated mechanism that does not involve VEGFR1.

Key words: Insulin, RF / 6A, VEGFR1, VEGFR2, Angiogenesis