STUDIES ON HEMOGLOBIN METABOLISM. I. THE KINETIC PROPERTIES OF THE PLASMA HEMOGLOBIN POOL IN NORMAL MAN*

Abstract

Normal human hemoglobin labeled in vivo with radio-iron was infused intravenously into normal human subjects in nearly tracer amounts and the rate of plasma disappearance determined. These data, together with those for larger amounts of hemoglobin as reported in the literature, are in accordance with a proposed model in which the outflow from the plasma hemoglobin pool is limited through a series of reactions involving complex formation. The constants for the prediction of the outflow of hemoglobin for various concentrations of plasma hemoglobin are given on the basis of the proposed model. The data indicate that normally few red cells release hemoglobin intravascularly and that the plasma hemoglobin pool is a relatively unimportant pathway in normal hemoglobin metabolism.