骨研究ジャーナル
オープンアクセス

概要

Multiple Modes of Blood Coagulation

Gerard Marx

Background: The standard view of blood coagulation is based on a mechanism whereby cascade interactions of clotting factors generate thrombin, which converts soluble fibrinogen into an insoluble clot.
Objective: Review the modalities by which soluble fibrinogen transforms into an insoluble matrix, the basis of blood coagulation.
New concept: An alternate process is operative that can transform fibrinogen, based on reactions with free
radicals. Such could be generated by the release of ascorbate by activated platelets. Ions of multivalent metals, such as Cu+2 or Fe+2 bound to fibrinogen, react with the ascorbate (a reductant in a Fenton reaction) to generate H2O2 and reactive oxygen species. Alternately, γ-irradiation which generates H2O2 could generate such species. Supportive evidence and references are cited.
Conclusion: An expanded blood clotting schema is presented that incorporates the classic (via thrombin) as well as alternate (free radical) pathways by which fibrinogen can be converted into an insoluble clot. This new schema is discussed within the context of γ-irradiation or dietary ascorbate as instigants of free-radical induced clotting events, of particular relevance to airplane pilots, divers, submariners, astronauts and patients not responding to classic anticoagulation (heparin, Coumadin) therapy.
Keywords: Mechanisms; Thrombin; Vitamin C; Free