title: Protein kinase C-mediated ATP stimulation of Na(+)-ATPase activity in LLC-PK1 cells involves a P2Y2 and/or P2Y4 receptor.
abstract: ATP-activated P2Y receptors play an important role in renal sodium excretion. The aim of this study was to evaluate the modulation of ATPase-driven sodium reabsorption in the proximal tubule by ATP or adenosine (Ado). LLC-PK1 cells, a model of porcine proximal tubule cells, were used. ATP (10(-6)M) or Ado (10(-6)M) specifically stimulated Na(+)-ATPase activity without any changes in (Na(+)+K(+))-ATPase activity. Our results show that the Ado effect is mediated by its conversion to ATP. Furthermore, it was observed that the effect of ATP was mimicked by UTP, ATPγS and 2-thio-UTP, an agonist of P2Y2 and P2Y4 receptors. In addition, ATP-stimulated Na(+)-ATPase activity involves protein kinase C (PKC). Our results indicate that ATP-induced stimulation of proximal tubule Na(+)-ATPase activity is mediated by a PKC-dependent P2Y2 and/or P2Y4 pathway. These findings provide new perspectives on the role of the effect of P2Y-mediated extracellular ATP on renal sodium handling.
authors.affiliation: Instituto Federal de Educação, Ciência e Tecnologia do Rio de Janeiro, Campus Realengo, 21715-000 Rio de Janeiro, RJ, Brazil.
authors.forename: M
authors.initials: M
authors.lastname: Wengert
authors.forename: M C
authors.initials: MC
authors.lastname: Ribeiro
authors.forename: T P
authors.initials: TP
authors.lastname: Abreu
authors.forename: R
authors.initials: R
authors.lastname: Coutinho-Silva
authors.forename: L R
authors.initials: LR
authors.lastname: Leão-Ferreira
authors.forename: A A S
authors.initials: AA
authors.lastname: Pinheiro
authors.forename: C
authors.initials: C
authors.lastname: Caruso-Neves
mesh_terms: D000241:Adenosine / Q000378:metabolism; D000251:Adenosine Triphosphatases / Q000378:metabolism*; D000255:Adenosine Triphosphate / Q000378:metabolism*; D000818:Animals; D027682:Cation Transport Proteins / Q000378:metabolism*; D002460:Cell Line; D004789:Enzyme Activation; D007687:Kidney Tubules, Proximal / Q000166:cytology / Q000378:metabolism; D011493:Protein Kinase C / Q000378:metabolism*; D018048:Receptors, Purinergic P2 / Q000378:metabolism*; D058473:Receptors, Purinergic P2Y2 / Q000378:metabolism*; D012964:Sodium / Q000378:metabolism; D000254:Sodium-Potassium-Exchanging ATPase / Q000378:metabolism; D013552:Swine
chemical_list: D027682:Cation Transport Proteins; D018048:Receptors, Purinergic P2; D058473:Receptors, Purinergic P2Y2; C104749:purinoceptor P2Y4; D000255:Adenosine Triphosphate; D012964:Sodium; D011493:Protein Kinase C; D000251:Adenosine Triphosphatases; C021838:sodium-translocating ATPase; D000254:Sodium-Potassium-Exchanging ATPase; D000241:Adenosine