title: Lymphocyte-derived adrenocorticotropin is insufficient to stimulate adrenal steroidogenesis in hypophysectomized rats.
abstract: Cells of the immune system can produce and respond to peptide hormones associated with the endocrine system. However, the physiological significance of these endocrine-immune interactions is not known. It has been postulated that cells of the immune system, when stimulated with viruses that induce interferon-alpha, produce sufficient levels of ACTH to stimulate adrenal steroidogenesis and, thus, function as an auxiliary source of ACTH that may have a role in the response to stress. However, we have confirmed that levels of ACTH-related peptides produced by immunocompetent cells are far lower than those produced by the pituitary, raising questions about the ability of lymphocyte-derived ACTH to stimulate adrenal function. Furthermore, we have rigorously examined this issue using intact and hypophysectomized rats treated with Newcastle disease virus. Although high levels of interferon-alpha were produced by both intact and hypophysectomized rats, and the plasma corticosterone concentration increased dramatically in intact animals, corticosterone remained undetectable in hypophysectomized rats. The lack of a corticosterone response in these animals was not due to adrenal insensitivity to ACTH, as shown by a normal rise in corticosterone following Cosyntropin injection 8 h after hypophysectomy. The findings demonstrate that levels of ACTH produced by nonpituitary sources in response to viral infection are not sufficient to stimulate adrenal steroidogenesis.
authors.affiliation: Division of Rheumatology/Immunology, Vanderbilt University Medical Center, Nashville, Tennessee 37232.
authors.forename: N J
authors.initials: NJ
authors.lastname: Olsen
authors.forename: W E
authors.initials: WE
authors.lastname: Nicholson
authors.forename: C R
authors.initials: CR
authors.lastname: DeBold
authors.forename: D N
authors.initials: DN
authors.lastname: Orth
mesh_terms: D000305:Adrenal Cortex Hormones / Q000096:biosynthesis*; D000311:Adrenal Glands / Q000378:metabolism*; D000324:Adrenocorticotropic Hormone / Q000502:physiology*; D000818:Animals; D002460:Cell Line; D003345:Corticosterone / Q000096:biosynthesis; D006801:Humans; D007016:Hypophysectomy; D007030:Hypothalamo-Hypophyseal System / Q000502:physiology; D008214:Lymphocytes / Q000502:physiology*; D009522:Newcastle disease virus / Q000502:physiology; D010913:Pituitary-Adrenal System / Q000502:physiology; D011333:Pro-Opiomelanocortin / Q000235:genetics; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats
chemical_list: D000305:Adrenal Cortex Hormones; D012333:RNA, Messenger; D011333:Pro-Opiomelanocortin; D000324:Adrenocorticotropic Hormone; D003345:Corticosterone