α2u Globulin is an androgen-inducible rat urinary protein of hepatic origin. On account of its relatively low molecular weight (26 400), α2u globulin is rapidly filtered through the kidneys and is released into the urine. This androgen-dependent protein is normally synthesized only in adult male rats but it can be induced in spayed females by treatment with androgen. The synthesis of α2u globulin is strongly inhibited by the oestrogens (Roy, Neuhaus & Harmison, 1966; Roy & Neuhaus, 1967; Roy & Raber, 1972). The androgen-dependent synthesis of α2u globulin requires the presence of the pituitary gland (Kumar, Roy & Axelrod, 1969). The pituitary gland exerts its influence on the hepatic synthesis of α2u globulin directly through growth hormone and indirectly through its control over the adrenal cortex and the thyroid gland (Roy, 1973a). Non-specific stimulation of the various post-transcriptional processes in protein synthesis has been