Endocrine and behavioral changes in depression after thyrotropin-releasing hormone (TRH). Alteration by pretreatment with thyroid hormones.

The effects of pretreatment with a single dose of thyroid hormones (TH) on the subsequent endocrine and behavioral response to TRH was evaluated in unipolar depressed women. TH pretreatment altered neither serum levels of thyroid hormones nor the TRH-induced TSH response. It antagonized, however, the behavioral response to TRH. This was apparent in 2 self-assessment scales but not in an objective rating scale. Taken together the data suggest that (a) there is an impaired pituitary response to TH feedback in depressed patients; (b) TH pretreatment may affect self-assessment of behavioral effects of TRH in depression.