Basic fibroblast growth factor up-regulates the expression of vascular endothelial growth factor in primary cultured rat astrocytes

AIM: To examine the effect of recombinant human basic fibroblast growth factor(bFGF) on the expression of vascular endothelial growth factor (VEGF) in primary cultured rat astrocytes. METHODS: Semiquantification PCR (SQ-PCR) and immunocytochemistry were used to investigate the effect of bFGF on VEGF mRNA level and protein level, respectively. RESULTS: Treatment with bFGF dose-dependently increased the VEGF mRNA level in astrocytes. The up-regulation of VEGF mRNA induced by bFGF (10 mu g/L) was detected as short as 3-h treatment. The increase of VEGF mRNA level reached the maximum after 24-h treatment with bFGF. The immunocytochemical staining showed that the VEGF protein level in astrocytes also increased after the cells were incubated with bFGF. CONCLUSION: bFGF induced a marked time- and concentration-dependent increase in VEGF expression in primary cultured astrocytes, suggesting that the effect of bFGF on angiogenesis in brain may act partly by up-regulating VEGF expression in astrocytes.