Differential regulation of thyrotropin releasing hormone receptors in neoplastic rodent mammotropic, adrenocorticotropic and thyrotropic pituitary cells in culture.

Modulation of the concentration of receptors for thyrotropin releasing hormone (TRH) is different in neoplastic mammotropic, adrenocorticotropic, and thyrotropic pituitary cells in culture. Hydrocortisone increases the TRH receptor concentration in mammotropic and adrenocorticotropic cells but has no effect in thyrotropic cells. B-estradiol increases the TRH receptor number in mammotropic cells but has no effect in adrenocorticotropic and thyrotropic cells. Both TRH and T3 decrease the receptor concentration in all three cell types.