Beta3-adrenergic receptors modulate vascular endothelial growth factor release in response to hypoxia through the nitric oxide pathway in mouse retinal explants

Naunyn Schmiedebergs Arch Pharmacol. 2013 Apr;386(4):269-78. doi: 10.1007/s00210-012-0828-x. Epub 2013 Jan 3.


Beta-adrenergic receptors (β-ARs) play a role in angiogenic processes that characterize neovascularization-associated retinal diseases, but the role of β3-ARs has not been disclosed yet. We used ex vivo retinal explants to investigate the role of β3-ARs in regulating vascular endothelial growth factor (VEGF) release associated with hypoxia. Whether nitric oxide (NO) mediates β3-AR regulation of VEGF release was also investigated. β3-AR activation was obtained using BRL 37344, whereas SR59230A, L-748,337, or specific siRNAs were used to block β3-ARs. Pharmacological approaches were used to interfere with the NO pathway. Western blot was used to determine β-AR levels. Enzyme-linked immunosorbent assay was used to measure VEGF release. NO production was assessed by a colorimetric assay. We found that hypoxia upregulates β3-ARs. In addition, we observed that β3-AR activation with BRL 37344 increases VEGF release in response to hypoxia. Either β3-AR blocker or β3-AR silencing downregulates drastically hypoxic levels of VEGF. With experiments using NO synthase (NOS) blockade with L-NAME, NOS activation with fluvastatin or NO supplementation with SNAP, we demonstrated that β3-ARs and VEGF are functionally coupled via the NO pathway. In summary, the data presented here support the assumption that β3-ARs are involved in the regulation of angiogenic responses to hypoxia through the NO signalling, a key pathway in hypoxic/ischemic diseases. Although extrapolation of these data to the human situation is difficult, these findings may help to explore the possible role of β3-ARs in vascularization-associated disorders.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Hypoxia / metabolism
  • Mice
  • Mice, Inbred C57BL
  • Nitric Oxide / metabolism
  • Receptors, Adrenergic, beta-3 / metabolism*
  • Retina / metabolism*
  • Vascular Endothelial Growth Factor A / metabolism


  • Receptors, Adrenergic, beta-3
  • Vascular Endothelial Growth Factor A
  • vascular endothelial growth factor A, mouse
  • Nitric Oxide