title: Studies of an inhibitor of the thrombin-fibrinogen reaction localized in rat liver microsomes. Interference with the polymerization step.
abstract: A heat-stable, macromolecular inhibitor of the thrombin-fibrinogen reaction localized in rat liver microsomes has been shown to interfere with the polymerization step in the fibrinogen-fibrin conversion. The inhibitor had no effect on thrombin activity as measured with the synthetic, chromogenic substrate BZ-Phe-Val-Arg-pNA. The amount of fibrin formed and the release of fibrinopeptide A were not affected by the inhibitor. Recording of turbidity at 350 nm and 600 nm indicated an inhibition of the lateral aggregation of the end-to-end fibrin polymers. The inhibitor was localized in both the luminal and membrane fractions of the microsomes. The inhibitor activity was not affected by warfarin treatment of the rats.
mesh_terms: D000818:Animals; D004791:Enzyme Inhibitors / Q000032:analysis; D005337:Fibrin / Q000378:metabolism; D005340:Fibrinogen / Q000378:metabolism*; D005344:Fibrinopeptide A / Q000037:antagonists & inhibitors; D008862:Microsomes, Liver / Q000201:enzymology*; D011108:Polymers; D051381:Rats; D013917:Thrombin / Q000378:metabolism*; D014859:Warfarin / Q000494:pharmacology
chemical_list: D004791:Enzyme Inhibitors; D011108:Polymers; D005344:Fibrinopeptide A; D014859:Warfarin; D005337:Fibrin; D005340:Fibrinogen; D013917:Thrombin