[Value of the test using TRH in the exploration of thyroid diseases]

The discovery and the synthesis of the thyrotropin-releasing hormone (T.R.H.) has given rise to a new test able to explore the function of the thyroid and the pituitary. Intravenous injection of T.R.H. determines a short elevation of T.S.H. in the plasma. In hyperthyroidism and in hot nodules the response is abolished. In hypothyroidism, the response depends on the localization of the lesion: exaggerated response in thyroid lesions, diminished or abolished response in pituitary problems, delayed response in hypothalamic lesions. This new test will definitely have an important diagnostic role in difficult clinical problems.