THE BINDING OF MYOGLOBIN BY PLASMA PROTEIN

Abstract
When added to dog plasma in vitro and in vivo, myoglobin was bound to plasma protein in a concentration which, maximally, averaged 21 ± 6 mg. per cent. Electrophoretically, bound myoglobin was separated from free myoglobin and migrated between alpha-2 and beta globulin. The electrophoretic characteristics of protein-bound myoglobin were similar to, although not identical with, those of protein-bound hemoglobin. The maximal binding capacity of plasma for myoglobin was less than for hemoglobin, which averaged 123 mg. per cent. At concentrations below the maximal binding capacity, from 15 to 50 per cent of the myoglobin was in the free, unbound state, differing from hemoglobin which was completely bound at all concentrations below the binding capacity.