Blockade of adenosine A2A receptors prevents protein phosphorylation in the striatum induced by cortical stimulation.
Previous studies have shown that cortical stimulation selectively activates extracellular signal-regulated kinase 1/2 (ERK1/2) phosphorylation and immediate early gene expression in striatal GABAergic enkephalinergic neurons. In the present study, we demonstrate that blockade of adenosine A2A receptors with caffeine or a selective A2A receptor antagonist counteracts the striatal activation of cAMP-protein kinase A cascade (phosphorylation of the Ser845 residue of the glutamate receptor 1 subunit of the AMPA receptor) and mitogen-activated protein kinase (ERK1/2 phosphorylation) induced by the in vivo stimulation of corticostriatal afferents. The results indicate that A2A receptors strongly modulate the efficacy of glutamatergic synapses on striatal enkephalinergic neurons.
Quiroz
César
C
Behavioral Neuroscience Branch, National Institute on Drug Abuse, Intramural Research Program, National Institutes of Health, Department of Health and Human Services, Baltimore, Maryland 21224, USA.
Gomes
Catarina
C
Pak
Arlene C
AC
Ribeiro
Joaquim A
JA
Goldberg
Steven R
SR
Hope
Bruce T
BT
Ferré
Sergi
S
D058917:Adenosine A2 Receptor Antagonists; D000818:Animals; D002540:Cerebral Cortex / Q000187:drug effects / Q000378:metabolism*; D003342:Corpus Striatum / Q000187:drug effects / Q000378:metabolism*; D004558:Electric Stimulation / Q000379:methods; D008297:Male; D010766:Phosphorylation / Q000187:drug effects; D051381:Rats; D017207:Rats, Sprague-Dawley; D043705:Receptor, Adenosine A2A / Q000502:physiology; D014970:Xanthines / Q000494:pharmacology
D058917:Adenosine A2 Receptor Antagonists; C113602:MSX 3 compound; D043705:Receptor, Adenosine A2A; D014970:Xanthines