title: Vasopressin, ATP and catecholamines differentially control potassium secretion in inner ear cell line.
abstract: A strict control of endolymph composition (high potassium, low sodium fluid) and volume is instrumental for a proper functioning of the inner ear. Alteration of endolymph homeostasis is proposed in the pathogenesis of Menière's disease. However, the mechanisms controlling endolymph secretion remain elusive. By using the vestibular EC5v cells, we provide evidence for the presence of vasopressin, catecholamine and purinergic signaling pathways, coupled to adenylate cyclase, phosphoinositidase C and Ca(2+) activation. We demonstrate that vasopressin and catecholamines stimulate while ATP inhibits apical potassium secretion by EC5v cells. These results open new interesting perspectives for the management of inner ear diseases.
authors.affiliation: UMR-S 867, Inserm, UFR de Médecine Paris Diderot, Paris, France.
authors.forename: Jérôme
authors.initials: J
authors.lastname: Nevoux
authors.forename: Marie
authors.initials: M
authors.lastname: Teixeira
authors.forename: Say
authors.initials: S
authors.lastname: Viengchareun
authors.forename: Claudine
authors.initials: C
authors.lastname: Cosson
authors.forename: Daniel
authors.initials: D
authors.lastname: Butlen
authors.forename: Marc
authors.initials: M
authors.lastname: Lombès
authors.forename: Evelyne
authors.initials: E
authors.lastname: Ferrary
mesh_terms: D000255:Adenosine Triphosphate / Q000494:pharmacology*; D000262:Adenylyl Cyclases / Q000378:metabolism; D000818:Animals; D015153:Blotting, Western; D020013:Calcium Signaling / Q000187:drug effects; D002395:Catecholamines / Q000494:pharmacology*; D002460:Cell Line; D000242:Cyclic AMP / Q000378:metabolism; D007758:Ear, Inner / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism*; D051379:Mice; D010727:Phosphoric Diester Hydrolases / Q000378:metabolism; D011188:Potassium / Q000378:metabolism*; D058470:Receptors, Purinergic P2Y / Q000378:metabolism; D017483:Receptors, Vasopressin / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014667:Vasopressins / Q000494:pharmacology*
chemical_list: D002395:Catecholamines; D058470:Receptors, Purinergic P2Y; D017483:Receptors, Vasopressin; D014667:Vasopressins; D000255:Adenosine Triphosphate; D000242:Cyclic AMP; D010727:Phosphoric Diester Hydrolases; C021491:glycerophosphoinositol glycerophosphodiesterase; D000262:Adenylyl Cyclases; D011188:Potassium