title: Thyroid hormones enhance hypoxia-induced erythropoietin production in vitro.
abstract: Effects of thyroid hormones on the production of erythropoietin (Epo) were investigated in isolated perfused rat kidneys and in the human hepatoma cell line, HepG2. Epo protein was measured by radioimmunoassay. L-triiodothyronine and L-thyroxine stimulated hypoxia-induced Epo formation both in the kidney and in HepG2 cells in a dose-dependent fashion. Quantitation of Epo mRNA by competitive polymerase chain reaction (PCR) showed that hypoxic HepG2 cells had three-fold higher Epo messenger RNA levels when treated with thyroid hormones for 3 hours. Measurements of oxygen consumption revealed that this effect was not due to an increase in the degree of hypoxia. Thus, apart from the known direct effect on erythroid precursors, thyroid hormones appear to stimulate erythropoiesis by a noncalorigenic increase in Epo production.
authors.affiliation: Physiologisches Institut I, Rheinischen Friedrich-Wilhelms-Universität Bonn, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Fandrey
authors.forename: H
authors.initials: H
authors.lastname: Pagel
authors.forename: S
authors.initials: S
authors.lastname: Frede
authors.forename: M
authors.initials: M
authors.lastname: Wolff
authors.forename: W
authors.initials: W
authors.lastname: Jelkmann
mesh_terms: D000818:Animals; D006528:Carcinoma, Hepatocellular / Q000737:chemistry / Q000378:metabolism / Q000473:pathology; D002478:Cells, Cultured; D004247:DNA / Q000235:genetics; D004305:Dose-Response Relationship, Drug; D004921:Erythropoietin / Q000032:analysis / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D000860:Hypoxia / Q000503:physiopathology*; D007668:Kidney / Q000737:chemistry / Q000166:cytology / Q000378:metabolism; D008113:Liver Neoplasms / Q000737:chemistry / Q000378:metabolism / Q000473:pathology; D008297:Male; D010101:Oxygen Consumption / Q000502:physiology; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000032:analysis / Q000235:genetics; D011863:Radioimmunoassay; D051381:Rats; D017207:Rats, Sprague-Dawley; D013974:Thyroxine / Q000494:pharmacology*; D014284:Triiodothyronine / Q000494:pharmacology*; D014407:Tumor Cells, Cultured; D000509:alpha-Fetoproteins / Q000032:analysis / Q000235:genetics / Q000378:metabolism
chemical_list: D012333:RNA, Messenger; D000509:alpha-Fetoproteins; D014284:Triiodothyronine; D004921:Erythropoietin; D004247:DNA; D013974:Thyroxine