EFFECTS OF CORTICOSTERONE IN-VIVO AND IN-VITRO ON ADRENOCORTICOTROPICHORMONE PRODUCTION BY CORTICOTROPIN-RELEASING FACTOR-STIMULATED LEUKOCYTES

Corticotropin releasing factor (CRF) and corticosterone have been show n to affect immune cell function. Previously, we have shown that CRF s timulates Immunoreactive adrenocorticotropic hormone (ACTH) production by leukocytes. In this study, splenic leukocytes from corticosterone- injected chickens failed to show a CRF-induced increase in ACTH produc tion. In addition, corticosterone In vitro inhibited the production of leukocyte ACTH as well as the stimulatory effect of CRF on splenic le ukocyte ACTH production. These findings show that, as with anterior pi tuitary ACTH production, CRF-stimulated leukocyte ACTH production is i nhibited by glucocorticoids.