Matrigel Plug Angiogenesis Assay

Plugs of 0.5 mL Growth Factor Reduced matrigel (356231, BD Biosciences, San Jose, CA, USA), supplemented with either 600 ng/mL recombinant murine FGF-2 (450-33, Peprotech, London, UK) and 3 U/mL heparin (Biochrom AG, L6510) or 200 ng/mL recombinant murine VEGF₁₆₅ (450-32, Peprotech, London UK) and 10 U/mL heparin, were s.c. injected into the flank of either WT or Cx37−/− mice. Matrigel plugs lacking growth factors were used as negative controls. WT mice were also injected with Growth Factor Reduced matrigel supplemented with 200 ng/mL VEGF, 10 U/mL heparin and 300 µM of either the ^37,43Gap27 peptide or its scrambled version. The plugs were removed 1 week later for evaluation of vascularization, as published [28 (link)]. Specifically, the macroscopic observations of all implanted plugs showed the presence of blood vessels, and the color difference of the plugs implanted in control mice and Cx37−/− mice paralleled a different hemoglobin content, providing an indirect, still reliable and commonly used indicator of angiogenesis [28 (link)].