METABOTROPIC GLUTAMATE RECEPTORS MEDIATE ACTIVATION OF NPY-Y-2 RECEPTOR EXPRESSION IN THE RAT DENTATE GYRUS

NEUROPEPTIDE Y-Y-2 receptor mRNA and binding were investigated after l ocal injection of excitatory amino acid receptor agonists into the rat hippocampus. The general metabotropic glutamate receptor (mGluR) agon ist (1S,3R)ACPD (200 and 400 nmol) and the group I mGluR agonist DHPG (50 nmol) enhanced Y-2 receptor mRNA levels in granule cells (by up to 470%) and [I-125]PYY(3-36) binding in messy fibers. The group I mGluR antagonist 4-CPG (200 nmol) inhibited the action of (1S,3R)ACPD. On t he other hand, AMPA and NMDA enhanced Y-2 receptor expression only at neurodegenerative doses (> 0.3 and 3 nmol, respectively). It is sugges ted that seizure-induced Y-2 receptor expression in granule cells may be mediated by group I mGluRs. NeuroReport 9: 2347-2351 (C) 1998 Rapid Science Ltd.