Growth factor for endothelial cells. VEGF-B167 binds heparin and neuropilin-1 whereas the binding to neuropilin-1 of VEGF-B186 is regulated by proteolysis. Homodimer; disulfide-linked. Can also form heterodimer with VEGF. Secreted but remains associated to cells or to the extracellular matrix unless released by heparin. Additional isoforms seem to exist. Expressed in all tissues except liver. Highest levels found in heart, skeletal muscle and pancreas. VEGF-B186 is O-glycosylated. Belongs to the PDGF/VEGF growth factor family.