CONCENTRATION OF PROTHROMBIN AND Ac-GLOBULIN IN VARIOUS SPECIES

Abstract
Analyses of plasmas of selected spp. indicate that the relative concn. of plasma Ac-globulin, in units/cc, is as follows: man 12-17, dog 150-200, cat 130-170, rabbit 150-300 and guinea pig 30-40. The conversion from plasma Ac-globulin to serum Ac-globulin was shown to take place in human, dog, rabbit, guinea pig and cow plasma; however, the stability of serum Ac-globulin varies considerably in the spp. studied. In man and dog sera, Ac-globulin is extremely labile, while in bovine and rabbit sera the factor is much more stable. The reported differences in the concns. of Ac-globulin in the various spp. offer at least a partial explanation for the reported discrepancies of prothrombin values obtained by the 1-stage and the 2-stage methods, the latter, when modified, giving the correct values.