Affective State and Thyrotropin and Prolactin Responses After Repeated Injections of Thyrotropin-Releasing Hormone in Depressed Patients

Eight patients with serious depression were given 1000 µg. of thyrotropin-releasing hormone (TRH) or saline intravenously for three days in a double-blindstudy. All patients then received 1000 µg. of TRH daily for the next seven days. The group receiving saline showed the greatest improvement; only one patient improved substantially while receiving TRH. Plasma thyrotropin and prolactin responses to TRH were distinctly diminished in three of the most severely depressed patients. The authors suggest that in depression the primary value of TRH may be as a diagnostic tool in differentiating among various types of depression.