RT Journal A1 Prange AJ, Jr, Loosen PT, Wilson IC, Meltzer HY, Fang VS T1 BEhavioral and endocrine responses of schizophrenic patients to trh (protirelin) JF Archives of General Psychiatry JO Archives of General Psychiatry YR 1979 FD September 1 VO 36 IS 10 SP 1086 OP 1093 DO 10.1001/archpsyc.1979.01780100056005 UL http://dx.doi.org/10.1001/archpsyc.1979.01780100056005 AB • We studied the effects of intravenous protirelin (thyrotropin-releasing hormone) in 17 schizophrenic patients and 17 normal subjects. A total of 12 patients received protirelin, 0.5 mg, and, on another occasion, niacin, 2 mg, in a double-blind, crossover design. Both behavioral and endocrine data were collected. Five patients received protirelin in an open trial; only endocrine data were collected. Protirelin caused about a 50% prompt decrease in psychotic symtpoms. Patients then tended slowly to experience a relapse. Side effects were about as infrequent after protirelin as after niacin. We assayed serum prolactin (PRL), growth hormone (GH), thyroid-stimulating hormone (TSH), L-triiodothyronine (T3) and thyroxine (T4). Free T4 (FT4) index was calculated. The values for PRL, GH, and TSH at baseline and after protirelin stimulation were normal. Patients showed lower T3 values at baseline, but a brisker T3 response to protirelin, than controls. Their FT4 indices were higher at baseline. Patients showed diminished T4 binding sites rather than increased total T4. The causes of these alterations in thyroid dynamics are unidentified.