DIETARY AND DOSAGE FACTORS AFFECTING THYROXINE INHIBITION OF ESTROGEN-INDUCED LIPEMIA IN THE CHICK

Abstract

IT HAS been repeatedly demonstrated that estrogen administration induces a marked lipemia in young chicks (Lorenz et al., 1938) (Zondek and Marx, 1939). Fleischmann and Fried demonstrated that thyroxine could effectively inhibit the hypercholesterolemia seen in estrogen-treated chicks (Fleischmann and Fried, 1945). They also noted that this interference by thyroxine with the expected chemical changes in the serum did not alter the tissue-growth response to estrogen in the chick oviduct. The present report includes observations which indicate: (a) that the degree of thyroxine inhibition of estrogen-induced lipemia in young chicks is quantitatively limited by the dosage of thyroxine, (b) that the thyroxine effect is not mediated by an excessive demand for factors of the B-complex created by the hyperthyroid state, (c) that the oviduct response to estrogen stimulation is quantitatively unaffected by simultaneous thyroxine administration,