Hypoxanthine Dehydrogenase in the Developing Chick Embryonic Kidney

Abstract

The activity of Hypoxanthine Dehydrogenase was determined in the meso- and metanephric renal tissue of the chick embryo and related to the amount of soluble protein in these tissues during successive developmental stages. The period of most rapid increase of specific activity occurred at 6-7 days in the meso-nephros and at 13-15 days in the metanephros. The highest specific activity was obtained on the 14th day in the mesonephric tissue which in the subsequent period of incubation exhibited decreasing hypoxanthine dehydrogenase activity. The metanephric tissue, which becomes the functional kidney of the adult attained a plateau of hypoxanthine dehydrogenase activity by the 16th day. The differentiation of the embryonic kidneys with respect to hypoxanthine dehydrogenase activity reported in these studies is well correlated with previous findings of renal function in the growing embryo studied by excretion of dyes by the renal tubules.