title: Contribution of chemical 6-O-sulfation of the aminodeoxyhexose residues in whale heparin with high affinity for antithrombin III to its anticoagulant properties.
abstract: The tributylammonium salt of whale (Balaenoptera borealis L.) intestinal heparin with high affinity for antithrombin III, whose degrees of sulfate-substitution in D-glucosamine and L-iduronic acid residues are GlcNS 0.738, GlcN6S 0.384, and IdoA2S 0.510 mol, was reacted with 2.5, 5.0, or 10.0 mol of pyridine-sulfur trioxide/mol of available hydroxyl groups in N,N-dimethylformamide at -10 degrees C for 1 h. Both chemical and NMR spectroscopic analyses revealed that an exclusive 6-O-sulfation of the D-glucosamine residues proceeded, according to the amount of the sulfating reagent used (GlcN6S: 0.476, 0.585, and 0.641 mol, respectively), the degree of sulfation at other natural substitution positions in the polysaccharide being unchanged, without any detectable unnatural sulfate-substitution. Biological examination of these products indicated that the 6-O-sulfation in the original whale heparin resulted in significant increases in blood clotting and anti-Factor IIa activities (maximal 43 and 82% increases, respectively), and in a moderate increase in the ability to bind antithrombin III, that is, in anti-Factor Xa activity and in intrinsic fluorescence enhancement of the protein (maximal 28 and 30% increases, respectively), together with a maximal 10% increase in the proportion of heparin species with higher affinity for antithrombin III, released with 1.0-3.0 M NaCl from antithrombin III-Sepharose.
authors.affiliation: School of Pharmaceutical Sciences, Kitasato University, Tokyo.
authors.forename: H
authors.initials: H
authors.lastname: Uchiyama
authors.forename: A
authors.initials: A
authors.lastname: Metori
authors.forename: A
authors.initials: A
authors.lastname: Ogamo
authors.forename: K
authors.initials: K
authors.lastname: Nagasawa
mesh_terms: D000818:Animals; D000925:Anticoagulants; D000990:Antithrombin III / Q000032:analysis*; D002417:Cattle; D002591:Cetacea / Q000378:metabolism*; D005453:Fluorescence; D005944:Glucosamine / Q000031:analogs & derivatives* / Q000032:analysis; D006493:Heparin / Q000032:analysis* / Q000494:pharmacology; D009682:Magnetic Resonance Spectroscopy; D013431:Sulfates / Q000032:analysis; D013552:Swine; D013696:Temperature; D014907:Whales / Q000378:metabolism*
chemical_list: D000925:Anticoagulants; D013431:Sulfates; C047200:1-deoxyglucosamine; D000990:Antithrombin III; D006493:Heparin; D005944:Glucosamine