title: Administration of adrenocorticotropic hormone (ACTH) enhances Fos expression in the rat adrenal cortex.
abstract: The effect of ACTH on the expression of Fos in rat adrenal glands was investigated immunocytochemically at both light and electron microscopic levels. An approximately 4-fold increase in the number of Fos-positive cortical cells per unit area of the adrenal cortex was found 45 min following a single injection of ACTH (i.v., 2 IU/kg b.w.), as compared with the control animals. The number of immunoreactive cells reached a maximum 90 min after ACTH injection and remained high 150 min after the injection. However, 5 h following the injection it declined significantly. At the ultrastructural level, the ACTH-induced Fos-like immunoreactivity was localized in the nuclei of cortical cells, exclusively confined to the nuclear regions associated with the euchromatin. The result that ACTH enhances Fos-like immunoreactivity suggests that ACTH is involved in c-fos induction in adrenal cortical cells. The characteristic intracellular localization of Fos-like immunoreactivity implies that Fos, once synthesized, may be rapidly translocated into the nuclei of the cells, where it participates in transcriptional regulation of genetic events.
authors.affiliation: Department of Public Health, Tampere University, Finland.
authors.forename: G A
authors.initials: GA
authors.lastname: Yang
authors.forename: J
authors.initials: J
authors.lastname: Koistinaho
authors.forename: M
authors.initials: M
authors.lastname: Iadarola
authors.lastname: Shenhua-Zhu
authors.forename: A
authors.initials: A
authors.lastname: Hervonen
mesh_terms: D000302:Adrenal Cortex / Q000187:drug effects / Q000378:metabolism* / Q000648:ultrastructure; D000324:Adrenocorticotropic Hormone / Q000494:pharmacology*; D000818:Animals; D002467:Cell Nucleus / Q000378:metabolism; D003593:Cytoplasm / Q000378:metabolism; D006651:Histocytochemistry; D007124:Immunoenzyme Techniques; D007700:Kinetics; D008297:Male; D016253:Microscopy, Immunoelectron; D011518:Proto-Oncogene Proteins / Q000096:biosynthesis*; D016760:Proto-Oncogene Proteins c-fos; D051381:Rats; D011919:Rats, Inbred Strains
chemical_list: D011518:Proto-Oncogene Proteins; D016760:Proto-Oncogene Proteins c-fos; D000324:Adrenocorticotropic Hormone