Heparan sulphate with no affinity for antithrombin III and the control of haemostasis

FEBS Letters

Ellis, Vincent¹  Kakkar, Vijay V.¹  Scully, Michael F.¹ 

[1] Thrombosis Research Unit, King's College School of Medicine & Dentistry, Denmark Hill, London SE5 8RX, England

关键词: Heparan sulfate;    Dermatan sulfate;    Antithrombin III;    Hemostasis;   

DOI  :  10.1016/0014-5793(88)81020-2

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Heparan sulphate with no affinity for antithrombin III (ATIII) was observed to cause acceleration of the factor Xa:ATIII interaction by 1100-fold (k ₂, 7 × 10⁷ M⁻¹·min⁻¹) and the prothrombinase:ATIII interaction by 2900-fold (k ₂, 2.5 × 10⁷ M⁻¹·min⁻¹). Although high-affinity heparan sulphate catalyzed higher acceleration and at lower concentration, in natural mixtures of the two forms the activity of the no affinity form predominated. Heparan sulphate had no significant effect on the thrombin:ATIII interaction but inhibited its potentiation by heparin (K _d 0.3 μM). From the estimated concentration of heparan sulphate on the endothelial cell surface it is proposed that the non-thrombogenic property of blood vessels is due to the acceleration of the factor Xa or prothrombinase:ATIII interaction by the greater mass of surface-bound heparan sulphate rather than by the much smaller proportion of heparin-like molecules (with high affinity for antithrombin III) which may be present.

【 授权许可】

Unknown