[Reflex reaction of the anticlotting system to DIP-alpha-thrombin devoid of blood clotting activity]

Injection of DFP-alpha-thrombin deprived of the blood coagulating activity into the systemic circulation of rats leads to mobilization of the humoral part of the anticoagulating system. providing high level of the anticoagulating and non-enzymatic fibrinolytic activity. This effect is not followed by increasing of soluble fibrin monomer complexes with fibrinogen or its degradation products concentration, suggesting absence of alpha-thrombin in the circulation. Perfusion of humorally isolated but retaining innervation carotid sinus of rabbit with the DFP-alpha-thrombin changes coagulability in the nonenzymatic fibrinolysis. The data on reflex activation of the anticoagulating system by the DFP-alpha-thrombin suggest the leading role of substrate binding site of the thrombin active in its physiological function.