title: Protamine sulfate stimulates degradation of factor Xa and the factor Xa-antithrombin complex.
abstract: The effect of protamine sulfate on factor Xa (FXa) and the factor Xa-antithrombin complex was studied via SDS-PAGE and Western blot analysis. Human factor Xa [(FXaα) ∼52 kDa, FXaβ ∼47 kDa] and human antithrombin (AT ∼55 kDa) form a primary (1°) complex at 109 and 104 kDa, a secondary (2°) complex at 99 and 95 kDa, and a tertiary (3°) complex at 66 and 62 kDa, as detected with polyclonal anti-FXa and anti-AT antibodies. Addition of protamine sulfate stimulates a transformation from free FXaα to FXaβ and degradation thence to inactive FXaγ (∼30 kDa), as well as transformation of FXaα-AT complexes to FXaβ-AT complexes. Additionally, protamine sulfate promotes digestive degradation from 1° to 3° complexes and FXaγ by the active enzyme. It further promotes reduction in total complex formation as a function of stimulation of hydrolysis of FXa moieties from the complex, thereby generating ATM. Protamine sulfate effects are proportional to the protamine sulfate concentration.
authors.affiliation: Departments of Biological Sciences and Chemistry, Bowling Green State University, Bowling Green, OH 43403, USA.
authors.forename: Martin H
authors.initials: MH
authors.lastname: Coggin
authors.forename: Rebecca
authors.initials: R
authors.lastname: Ahl
authors.forename: Amie
authors.initials: A
authors.lastname: Roland
authors.forename: Doris
authors.initials: D
authors.lastname: Beck
authors.forename: Arthur S
authors.initials: AS
authors.lastname: Brecher
mesh_terms: D000906:Antibodies / Q000276:immunology / Q000378:metabolism; D000991:Antithrombins / Q000276:immunology / Q000378:metabolism*; D015153:Blotting, Western; D004305:Dose-Response Relationship, Drug; D004591:Electrophoresis, Polyacrylamide Gel; D015951:Factor Xa / Q000276:immunology / Q000378:metabolism*; D006801:Humans; D006868:Hydrolysis / Q000187:drug effects; D008970:Molecular Weight; D011479:Protamines / Q000494:pharmacology*
chemical_list: D000906:Antibodies; D000991:Antithrombins; D011479:Protamines; D015951:Factor Xa