Changes in the Thyroid of Rats After Removal From Cold

Abstract
Male rats of the Wister strain exposed to cold (3[degree]C) for 7 days and then transferred from cold to normal environment temperatures (24[degree]-26[degree]C) show a change in the structure of their thyroid gland from hyperplasia to normal histology as early as 6 hours after removal from cold. This was also observed 24 hours after removal from cold. The 24-hour I131 collection by the thyroid gland was not affected.