Dopamine promotes NMDA receptor hypofunction in the retina through D1 receptor-mediated Csk activation, Src inhibition and decrease of GluN2B phosphorylation.

Autor: Socodato, Renato, Santiago, Felipe N., Portugal, Camila C., Domith, Ivan, Encarnação, Thaísa G., Loiola, Erick C., Ventura, Ana L. M., Cossenza, Marcelo, Relvas, João B., Castro, Newton G., Paes-de-Carvalho, Roberto
Zdroj: Scientific Reports; 1/20/2017, p40912, 1p
Abstrakt: Dopamine and glutamate are critical neurotransmitters involved in light-induced synaptic activity in the retina. In brain neurons, dopamine D1 receptors (D1Rs) and the cytosolic protein tyrosine kinase Src can, independently, modulate the behavior of NMDA-type glutamate receptors (NMDARs). Here we studied the interplay between D1Rs, Src and NMDARs in retinal neurons. We reveal that dopamine-mediated D1R stimulation provoked NMDAR hypofunction in retinal neurons by attenuating NMDA-gated currents, by preventing NMDA-elicited calcium mobilization and by decreasing the phosphorylation of NMDAR subunit GluN2B. This dopamine effect was dependent on upregulation of the canonical D1R/adenylyl cyclase/cAMP/PKA pathway, of PKA-induced activation of C-terminal Src kinase (Csk) and of Src inhibition. Accordingly, knocking down Csk or overexpressing a Csk phosphoresistant Src mutant abrogated the dopamine-induced NMDAR hypofunction. Overall, the interplay between dopamine and NMDAR hypofunction, through the D1R/Csk/Src/GluN2B pathway, might impact on light-regulated synaptic activity in retinal neurons. [ABSTRACT FROM AUTHOR]
Databáze: Complementary Index