THE EFFECT OF VARYING LEVELS OF THYROIDAL STIMULATION ON ADRENALS UNDER DIFFERENT ENVIRONMENTAL TEMPERATURES

Abstract

The effect of thyroidal stimulation on the weight of adrenals of the growing male mouse, kept at environmental temperatures of 24 and 30° C. for 3–4 weeks, has been studied. The administration of thyroxine (as iodinated protein) in sufficient dosages caused a significant increase in the weight of the adrenals of male mice kept at 24° C. whereas thiouracil caused a significant decrease. High environmental temperature alone caused a significant decrease in the weight of the adrenals, probably due to a decrease in the thyroid secretion rate which occurred at that temperature. The decrease in the weight of the adrenals was checked to some extent by the administration of very small doses of thyroxine; however, larger doses caused a decrease in the adrenal weight of the thyroprotein-treated mice. Hypothyroidism produced at 30° C. also resulted in a significant decrease in the weight of the adrenals.