TRH stimulation test

Some cells in the intermediate lobe of the pituitary gland secrete ACTH under the influence of TRH (thyrothropin-releasing hormone). When administering TRH, PPID horses will produce significantly more ACTH than healthy horses. This test can be used in case the ACTH test as well as the DST give questionable results. This test is suitable to detect PPID in an early stage.