Detection of Glycoproteins and Autoradiographic Localization of [3h]fucose in the Thyroidectomy Cells of Rat Anterior Pituitary Gland

W h e n the secretion of thyroid hormones is prevented by thyroidectomy or propyhhiouraci l (PTU) t reatment , the anter ior pi tui tary cells secreting the thyroid-st imulat ing hormone (TSH) become enlarged and their rough endoplasmic re t iculum (RER) forms large dilated cisternae (1, 2). These ceils are known as the thyroidectomy cells. The presence of granules in the dilated cisternae is a common finding 3 wk or more after suppression of thyroidal activity (1). These intracisternal granules are thought to be different from the secretory granules observed free in the cytoplasm (1). To our knowledge, little information is available on the composit ion of intracisternal granules. In this pre l iminary study, we report the histochemical detection of glycoproteins in the granules of thyroidectomy cells and the localization of [SH]fucose, which is known to be a terminal sugar (3), in the carbohydra te side chains of T S H (4). M A T E R I A L S A N D M E T H O D S