Unto U. Uotila

Rôle of Pituitary Stalk in Regulation of Thyrotropic and Thyroid Activity

Summary In rats with intact pituitary stalks, exposure to cold stimulates the thyrotropic function of the anterior pituitary and the thyroid gland. After pituitary stalk section, rats at room temperature produce enough thyrotropic hormone to keep the thyroid histologically normal. In rats similarly operated on, but exposed to cold, the thyroid reaction is lacking. It is concluded that the pathways in the pituitary stalk transmit impulses regulating the secretion of thyrotropic hormone in the emergency state of exposure to cold.