In recent years attention has been directed to the role of the thyroid gland in the metabolism of carotene and vitamin A. Drill and Truant (1947) reported that carotene administration failed to prevent xerophthalmia in thyroidectomized rats, whereas vitamin A supplementation cured the eye lesions. Moreover, Johnson and Baumann (1947), using liver storage of vitamin A as the criterion of conversion of carotene to vitamin A, found that hyperthyroid rats accumulated larger stores of vitamin A than normal rats receiving equivalent doses of carotene, but rats rendered hypothyroid by feeding either thiourea or thiouracil stored little vitamin A. Similar experiments by Kelley and Day (1948) also indicated that thiouracil interfered with the conversion of carotene to vitamin A in rats. Conversely, Wiese and associates (1948), using growth as a measure of carotene utilization, found that the ability of rats to convert carotene to vitamin A was not impaired by feeding thiouracil.
Proceedings of the Iowa Academy of Science
©1951 Iowa Academy of Science, Inc.
Allen, R. S.; Wise, G. H.; and Jacobson, N. L.
"Effect of Iodinated Casein and Thiouracil on the Concentrations of Carotenoids and Vitamin A in the Blood Plasma of Young Dairy Animals,"
Proceedings of the Iowa Academy of Science, 58(1), 235-243.
Available at: https://scholarworks.uni.edu/pias/vol58/iss1/26