title: Poly-L-lysine/heparin stimulates angiogenesis in chick embryo chorioallantoic membrane.
abstract: The effects of heparin on angiogenesis are controversial, with some studies claiming stimulatory and other studies claiming inhibitory effects. Since heparin in human plasma is complexed with basic peptides and proteins, we studied the angiogenic effect of complexes resulting by mixing poly-L-lysine (a basic heparin-binding polypeptide) and heparin. Angiogenesis was investigate by chorioallantoic membrane assay. In specimens treated with PBS (negative control), or poly-L-lysine, no significant vascular reaction was detectable. Heparin induced only moderate angiogenic response. However, neutral complexes purified from a mixture of poly-L-lysine and heparin (20/1, w/w) induced a very strong angiogenic response. These results demonstrate that the angiogenic effect of heparin was associated with neutralization of electric charge when the polysaccharide was complexed with a basic peptide.
authors.affiliation: Department of Anatomy, University of Firenze, viale Morgagni 50, Firenze, I-50134, Italy.
authors.forename: Stefania
authors.initials: S
authors.lastname: Pacini
authors.forename: Massimo
authors.initials: M
authors.lastname: Gulisano
authors.forename: Simonetta
authors.initials: S
authors.lastname: Vannucchi
authors.forename: Marco
authors.initials: M
authors.lastname: Ruggiero
mesh_terms: D000482:Allantois / Q000098:blood supply / Q000187:drug effects* / Q000196:embryology; D000818:Animals; D001681:Biological Assay; D002642:Chick Embryo; D002823:Chorion / Q000098:blood supply / Q000187:drug effects* / Q000196:embryology; D004357:Drug Synergism; D005780:Gelatin; D006493:Heparin / Q000737:chemistry / Q000494:pharmacology*; D019763:Heparin Lyase; D046911:Macromolecular Substances; D018919:Neovascularization, Physiologic / Q000187:drug effects*; D011107:Polylysine / Q000737:chemistry / Q000494:pharmacology*; D015503:Surgical Sponges
chemical_list: D046911:Macromolecular Substances; D011107:Polylysine; D005780:Gelatin; D006493:Heparin; D019763:Heparin Lyase