title: Anticoagulantly active heparin-like molecules from vascular tissue.
abstract: Mucopolysaccharides were isolated from calf cerebral microvasculature and calf aorta. The only complex carbohydrates that exhibited anticoagulant activity were heparin-like components. The biologic potencies of calf cerebral and aortic heparin-like species were 2.92 units/mg of anti-factor Xa activity and 2.85 units/mg of anti-factor IIa activity, as well as 0.56 unit/mg of anti-factor Xa activity and 0.19 unit/mg of anti-factor IIa activity, respectively. Additional experiments revealed that the anticoagulantly active aortic components were significantly present only within the intima. The above populations of heparin-like species were affinity fractionated with antithrombin. The highly active component obtained from calf cerebral microvasculature exhibited an anti-factor Xa activity of 40.7 units/mg as well as an anti-factor IIa activity of 36.8 units/mg, constituted about 4.2% of the initial mass of the starting material, and represented about 75% of the biologic potency of the starting material. The highly active component derived from calf aorta exhibited an anti-factor Xa activity of 55.4 units/mg as well as an anti-factor IIa activity of 11.3 units/mg, constituted about 0.3% of the initial mass of the starting material, and represented about 60% of the biologic potency of the starting material. The highly active cerebral microvascular species possessed a molecular weight and charge density similar to that of heparan sulfate whereas the highly active aortic species displayed a molecular weight and charge density equivalent to that of a hexadecasaccharide fragment of heparin.
mesh_terms: D000818:Animals; D000925:Anticoagulants; D000991:Antithrombins / Q000378:metabolism; D001011:Aorta / Q000032:analysis*; D002417:Cattle; D002560:Cerebrovascular Circulation; D002809:Chondroitin Sulfates / Q000302:isolation & purification; D005170:Factor X / Q000378:metabolism; D015951:Factor Xa; D006025:Glycosaminoglycans / Q000302:isolation & purification* / Q000494:pharmacology; D006493:Heparin / Q000302:isolation & purification*; D006801:Humans; D006820:Hyaluronic Acid / Q000302:isolation & purification; D008833:Microcirculation / Q000032:analysis; D013917:Thrombin / Q000378:metabolism
chemical_list: D000925:Anticoagulants; D000991:Antithrombins; D006025:Glycosaminoglycans; D005170:Factor X; D006820:Hyaluronic Acid; D006493:Heparin; D002809:Chondroitin Sulfates; D013917:Thrombin; D015951:Factor Xa