title: In vivo upregulation of adipocyte alpha 2-adrenoceptors by androgens is consequence of direct action on fat cells.
abstract: Adipose precursor cells from male hamsters were exposed to testosterone in primary culture. The effect of the sex steroid on alpha 2-adrenoceptor (AR) expression was studied. Testosterone enhanced alpha 2-AR expression during adipose conversion to an identical extent to that determined in vivo without modification of the differentiation state as estimated by glycerol-3-phosphate dehydrogenase activity. The expression of preadipocyte alha 2-ARs from female hamster was also submitted to the testosterone control. The upregulating effect was androgen specific, since only testosterone and dihydrotestosterone were efficient in inducing an increase of alpha 2-AR density, whereas estradiol, dexamethasone, progesterone, and androstenedione were without any action. To conclude, androgens act directly on fat cells by upregulating alpha 2-AR expression. The effects are not mediated by aromatization into estrogens and probably involve androgen receptor interactions.
authors.affiliation: Institut National de la Santé et de la Recherche Médicale Unité 317, Université Paul Sabatier, Centre Hospitalier Universitaire Rangueil, Toulouse, France.
authors.forename: A
authors.initials: A
authors.lastname: Bouloumie
authors.forename: P
authors.initials: P
authors.lastname: Valet
authors.forename: M
authors.initials: M
authors.lastname: Dauzats
authors.forename: M
authors.initials: M
authors.lastname: Lafontan
authors.forename: J S
authors.initials: JS
authors.lastname: Saulnier-Blache
mesh_terms: D017667:Adipocytes / Q000187:drug effects / Q000378:metabolism*; D000728:Androgens / Q000494:pharmacology*; D000818:Animals; D006224:Cricetinae; D004305:Dose-Response Relationship, Drug; D005260:Female; D008297:Male; D008647:Mesocricetus; D011942:Receptors, Adrenergic, alpha / Q000187:drug effects / Q000378:metabolism*; D013234:Stem Cells / Q000187:drug effects / Q000378:metabolism*; D013739:Testosterone / Q000494:pharmacology; D015854:Up-Regulation
chemical_list: D000728:Androgens; D011942:Receptors, Adrenergic, alpha; D013739:Testosterone