title: Interleukin regulation of prolactin and corticotropin from pituitary adenoma.
abstract: Recent findings indicate that lymphokines, leukocyte-derived hormones, interact with the hypothalamic-pituitary axis. We examined the role of neurotrophic lymphokines in the neuroendocrine system. Specifically, the action of Interleukin (IL)-1b, IL-2 and IL-6 upon the anterior pituitary hormones, growth hormone (GH), prolactin (PRL) and adrenocoticotropic hormone (ACTH) were studied in rodent pituitary adenoma cell lines. Hormone release by GH and PRL-producing rat adenoma cells (GH3) and ACTH-producing mouse adenoma cells (AtT-20) was analyzed by radioimmunoassay (RIA). Recombinant (r) IL-1beta decreased PRL release from GH3 in a dose-dependent fashion. IL-1 inhibition of PRL production occurred in parallel with IL-1 inhibition of DNA synthesis in GH3 as measured by [(3)H] thymidine incorporation. This result strongly indicates that IL-1 alters PRL production by adenoma cells at the translational level. Low dose IL-2 (10 U/ml) enhanced ACTH production from AtT-20, but higher concentrations of IL-2 failed to affect the release of ACTH. IL-2 did not change the incorporation of [(3)H] thymidine in AtT-20. Previous studies showed that IL-1 and IL-6 induce a significant secretion of ACTH via the hypothalamic-pituitary axis. However, IL-1 and IL-6 failed to affect ACTH secretion by AtT-20. Blood-derived cytokines have direct effects on hormone secretion by pituitary adenoma cells in vitro.
authors.affiliation: Departments of Neurosurgery and Immunology, Juntendo University School of Medicine, Tokyo, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Hishii
authors.forename: M
authors.initials: M
authors.lastname: Ebato
authors.forename: K
authors.initials: K
authors.lastname: Sato
authors.forename: K
authors.initials: K
authors.lastname: Okumura
authors.forename: T
authors.initials: T
authors.lastname: Nitta