THE INFLUENCE OF GROWTH ON THE PHOSPHORUS METABOLISM OF THE MOUSE AND THE EFFECT OF THYROXINE AT VARIOUS AGES

Abstract

In the growing mouse the rate of phosphorus turnover of the tissues studied decreases as the age of the animal increases. The decrease is greatest in the tibia, followed in descending order by brain, liver, spleen, kidney, blood, and heart. Thyroxine seems to have very little, if any, effect on the P turnover of the tissues of the mouse, with the exception of the tibia which in the older mice increases its P* to P ratio upon the adm. of thyroxine.