In vitro synthesis of coagulation factors by rat liver slices

Abstract

Rat liver slices prepared from a perfused liver were incubated in a bicarbonate-buffered salt medium; both tissue and medium were assayed for coagulation factors after various incubation periods. Although only traces of these substances were found in the freshly-excised tissue, large quantities of factor VII accumulated during the incubation. About 80% of this was in the tissue and 20% in the medium. Much smaller quantities of prothrombin were produced in the tissue but none could be detected in the incubation medium. Inhibition of both syntheses was caused by addition of NaCN, DNP, Dicumarol, warfarin, tromexan or CHCl3 to the flask, by incubation in the cold, or by substitution of a nitrogen atmosphere for oxygen. These syntheses apparently require intact cells since they did not occur in homogenized tissue nor in a system containing liver mitochondria and a protein-containing substrate. There was suggestive evidence that PTC production occurred but none that factor V or AHG was produced. It was concluded that further study of liver and other isolated tissues might provide a solution to the problem of the site of AHG synthesis.