Figure 4.

Vascular endothelial growth factor (VEGF) promoter activity and VEGF expression under conditions of cellular stress such as H₂O₂, heat, pH imbalance and serum deprivation. The values represent the mean ± standard error of the mean normalized to the control in each treatment group. (A) Green fluorescent protein (GFP) fluorescence intensity measured by flow cytometry revealed that mVP promoter activity was increased following treatment with H₂O₂ and long-term serum starvation but was not affected by temperature changes. Lowering or elevating the pH of the growth medium led to minor changes in GFP expression. (B) An elevated level of VEGF mRNA expression was observed in response to H₂O₂; however, heating, pH changes and serum starvation led to minor changes.