Upregulation of Vascular Endothelial Growth Factor by Angiotensin Ii in Rat Heart Endothelial Cells

Angiotensin II (All) was found to upregulate vascular endothelial growth factor (VEGF) gene expression in rat heart and mesenteric artery-derived endothelial cells in a dose and time-dependent manner. Maximal induction was achieved by 2 h after the addition of All, Addition of cyctoheximide superinduced and actinomycin D abolished the induction. In addition, the induction could be blocked by tosartan, an AT1 receptor antagonist and protein kinase C inhibitors, H7 and GF109203X. These results suggest that induction of VEGF transcripts by All is dependent on protein kinase C dependent pathway and de novo RNA synthesis. Immunoblot analysis revealed that VEGF was detectable in the conditioned medium 8 h after All stimulation. Our data suggest that All-induced VEGF plays a role in the change of endothelial cell permeability and angiogenesis in renovascular hypertension (Supported by Cécile Cox Quillen Chair of Geriatrics)