INVESTIGATIONS ON SOME CHEMICAL PROPERTIES OF PLASMA FIBRINOGENS AND FIBRINS FROM NORMAL AND COBALT-TREATED RABBITS

  • 1 January 1975
    • journal article
    • research article
    • Vol. 34  (10) , 1573-1588
Abstract
The sulfitolysis products of fibrinogens from normal and Co-treated rabbits (5 mg Co2+/kg body weight) were resolved by ion exchange chromatography on carboxymethyl-cellulose columns. The elution patterns of both fibrinogens showed a distinct heterogeneity of .gamma.-chains. A .gamma.-chain derivative from Co fibrinogen was distinguished electrophoretically from the corresponding one of normal fibrinogen because of its reduced electrophoretic mobility. Normal and Co fibrinogen did not differ from each other in their N-terminal (Val2Ala2Tyr2) and C-terminal (Pro1-2Val4-5) amino acid compositions related to a subunit structure of A.alpha.2B.beta.2.gamma.2, and their carbohydrate contents: neutral hexoses 1.21% (1.26%), N-acetyl hexosamines 1.16% (1.05%), N-acetyl neuraminic acid 1.19% (1.13%), values for Co fibrinogen in parentheses. The main amounts of carbohydrates were bound to .gamma.- and B.beta.-chains. The BrCN cleavage products from Co fibrinogen and its .gamma.- and B.beta.-chains showed other electrophoretic properties than the corresponding derivatives from normal fibrinogen. But BrCN split products of A.alpha.-chains of both fibrinogens were electrophoretically very similar. Spectrographic investigations of the S-sulfoderivates demonstrated a diminution of the absorption maximum near 282 nm of .gamma. and B.beta. derivatives of Co fibrinogen. A.alpha.-chains of both fibrinogens were not different from each other. Using autoradiography the highest 58Co binding was found in the .gamma.-chain with a reduced electrophoretic migration velocity but B.beta.- and .gamma.-chains with unchanged electrophoretic mobility bound only small amounts. A.alpha.-chains of Co fibrinogens were apparently not loaded with 58Co. .gamma.-Chain and .alpha.-chain cross-links were observed in normal fibrins stabilized by factor XIII. In Co fibrins a .gamma.-dimer formation was demonstrable without participation of .gamma.-chains with reduced electrophoretic mobility. A distinct .alpha.-chain cross-link was not demonstrated either. Earlier observed changes of physicochemical properties and biological behavior of Co fibrinogen apparently resulted from a complex binding of Co ions on specific structures of the fibrinogen molecule.