Role of Pituitary, Adrenal and Kidney in Several Thyroid Responses of Cold-Exposed Hamsters

Abstract
The role of the pituitary, adrenal and kidney was investigated in several of the thyroid responses to acute and chronic cold exposure. The pituitary gland is necessary for: a) maintenance of normal thyroid weight, histology and I131 uptake in hamsters housed at room temperature; b) survival of cold-exposed hamsters; and c) the increased thyroid I131 uptake occurring during cold exposure. The initial effects of cold exposure evoke a brief period of accelerated release of thyroidal I131 followed by complete inhibition of release Also during the period of initial cold exposure, I131 uptake is sharply depressed, probably because of an increase in renal elimination of iodide. This renal mechanism is independent of the adrenal glands but appears to require the presence of the pituitary.