The evidence of thyroliberin/triiodothyronine control of TSH secretory response from human peripheral blood monocytes cultured in vitro.

Immune system function has been shown to be under the influence of various neuromodulators and endocrine system peptides. This in vitro study describes the stimulatory effect of thyrotropin releasing hormone (thyroliberin, TRH) on thyrotropin (TSH) release from cultured human peripheral blood monocytes. The stimulatory effect of TRH on TSH release from monocytes is totally blocked by triiodothyronine (T3) administrations. These results indicate that TSH release from human monocytes is under the control of TRH/T3 mechanisms, similar to hypothalamic-pituitary-thyroid axis.