THE EXPRESSION OF NMDA RECEPTOR SUBUNITS IN RAT CNS IS DIFFERENTIALLY MODIFIED BY OUABAIN ADMINISTRATION.

G. RODRÍGUEZ DE LORES ARNAIZ; M. G. BERSIER

Charleston, Carolina sel Sur, EE.UU.

Congreso; XXXX Congreso de la Sociedad Americana de Neuroquímica (ASN); 2009

Sociedad Americana de Neuroquímica (ASN)

It has been reported that ouabain exerts neurotoxic action and that it activates the population of NMDA receptors. Herein the effect of ouabain on the expression of NMDA subunits was evaluated. Wistar rats of 250g were administered via i.c.v. with 0.1, 10 and 100 nmoles ouabain or saline solution (control). Two days later, membranes of cerebral cortex and hippocampus were isolated. Western blots with antibodies for the NMDA receptor subunits: GluN1; GluN2A; GluN2B; GluN2C and GluN2D were carried out. In cerebral cortex, GluN2D subunit increased 30% with 10 nmoles ouabain dose; with 100 nmoles ouabain GluN1 and GluN2D subunits enhanced 40% and 20%, respectively. In hippocampus, with the dose of 0.1 nmol ouabain, GluN1 subunit enhanced roughly 50% whereas GluN2B subunit decreased 30%. After administration of 10 nmoles ouabain dose, GluN2A, GluN2B and GluN2C subunits decreased 40%, 50% and 30%, respectively. With the dose of 100 nmoles ouabain, GluN1, GluN2A and GluN2B subunits diminished 10-20%. It is concluded that ouabain administration led to a differential regulation in the expression of NMDA subunits in rat cerebral cortex and hippocampus membranes. These results may be correlated with the modulator action of ouabain on NMDA receptor.