title: Secretion of a urodilatin-like immunoreactive (URO-like-IR) substance from a human kidney cell line (HEK-293).
abstract: The aim of this study was to explore whether sodium chloride is involved in the release of urodilatin from epithelial human embryonic kidney cells (HEK-293). Using a highly specific urodilatin radioimmunoassay combined with HPLC, gel chromatography, and a cyclic GMP generating bioassay, we demonstrate that HEK-293 cells release a biologically active 3.5 kD, urodilatin-like immunoreactive substance. To show the effect of sodium on urodilatin release, HEK-293 cells were incubated with cell culture buffer containing 120, 130, 140, and 150 mmol/l sodium, respectively. Urodilatin secretion from HEK-293 cells is increased to 176% when extracellular sodium is raised to 150 mmol/l (control: 120 mmol/l = 100%). There was no significant difference when exposing the cells to 140 mmol/l or 150 mmol/l sodium. It is suggested, that beside the known extrarenal factors influencing urodilatin secretion, high cephalic sodium and cardiac volume load, urodilatin secretion might also be regulated by an intrarenal sodium sensitive mechanism.
authors.affiliation: Bundesforschungsanstalt für Ernährung, Institut für Ernährungs-physiologie, Karlsruhe, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Bub
authors.forename: G
authors.initials: G
authors.lastname: Rechkemmer
authors.forename: D
authors.initials: D
authors.lastname: Hock
authors.forename: W G
authors.initials: WG
authors.lastname: Forssmann
mesh_terms: D015056:1-Methyl-3-isobutylxanthine / Q000494:pharmacology; D000818:Animals; D009320:Atrial Natriuretic Factor / Q000032:analysis / Q000096:biosynthesis* / Q000494:pharmacology; D001681:Biological Assay; D002021:Buffers; D002460:Cell Line; D002850:Chromatography, Gel; D002851:Chromatography, High Pressure Liquid; D003470:Culture Media; D006152:Cyclic GMP / Q000378:metabolism; D004622:Embryo, Mammalian; D004847:Epithelial Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D006801:Humans; D007668:Kidney; D010446:Peptide Fragments / Q000032:analysis / Q000096:biosynthesis* / Q000494:pharmacology; D011863:Radioimmunoassay; D051381:Rats; D012964:Sodium / Q000494:pharmacology
chemical_list: D002021:Buffers; D003470:Culture Media; D010446:Peptide Fragments; C056452:Ularitide; D009320:Atrial Natriuretic Factor; D012964:Sodium; D006152:Cyclic GMP; D015056:1-Methyl-3-isobutylxanthine