title: Rat hepatocytes express functional P2X receptors.
abstract: Extracellular ATP regulates many hepatic functions by stimulating purinergic receptors. Only the G protein-coupled P2Y receptors have been studied in hepatocytes. We investigated the functional expression of P2X receptors, the ATP-gated channels in rat hepatocytes. P2X4 and P2X7 transcripts and proteins were detected by RT-PCR and by both Western blotting and immunocytochemistry. High concentrations of ATP, and 2'-and 3'-O-(4-benzoylbenzoyl)-ATP the preferring agonist of P2X7, induced membrane blebbing and significant uptake of 4-[(3-methyl-2(3H)-benzoxazolylidene)methyl]-1-[3-(triethylammonio)propyl]diiodide, both of which were inhibited by oxidised ATP, a blocker of P2X receptors. These results provide evidence that P2X4 and P2X7 receptors are expressed and functional on rat hepatocytes, possibly playing an important role in the purinergic signaling complex in these cells.
authors.affiliation: INSERM, Université Paris-Sud, UMR-S757, Bâtiment 443, 15 rue Georges Clémenceau, Orsay Cedex, France. emmanuel.gonzales@gmail.com
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Gonzales
authors.forename: Sylvie
authors.initials: S
authors.lastname: Prigent
authors.forename: Aurélie
authors.initials: A
authors.lastname: Abou-Lovergne
authors.forename: Sylviane
authors.initials: S
authors.lastname: Boucherie
authors.forename: Thierry
authors.initials: T
authors.lastname: Tordjmann
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Jacquemin
authors.forename: Laurent
authors.initials: L
authors.lastname: Combettes
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D005455:Fluorescent Antibody Technique; D015870:Gene Expression; D022781:Hepatocytes / Q000378:metabolism*; D006801:Humans; D021122:Protein Subunits / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D018048:Receptors, Purinergic P2 / Q000235:genetics / Q000378:metabolism* / Q000502:physiology; D058469:Receptors, Purinergic P2X; D058848:Receptors, Purinergic P2X4; D058486:Receptors, Purinergic P2X7
chemical_list: C548226:P2RX4 protein, human; C546468:P2RX7 protein, human; C548228:P2rx4 protein, rat; C546470:P2rx7 protein, rat; D021122:Protein Subunits; D018048:Receptors, Purinergic P2; D058469:Receptors, Purinergic P2X; D058848:Receptors, Purinergic P2X4; D058486:Receptors, Purinergic P2X7