Effects of Glutamate Receptor Antagonists on Activation of ERK1/2 and CREB in Caudate-Putamen and Nucleus Accumbens of Food-Restricted Rats Food-restricted rats received i.c.v. injections of either saline vehicle, the AMPA antagonist DNQX (10 nmol), the group I mGluR antagonist AIDA (100 nmol), or NMDA antagonist MK-801 (100 nmol) prior to sacrifice. Lysates were immunoblotted with anti-phospho ERK1/2 or anti-ERK1/2 (top) and anti-phospho-CREB or anti-CREB (bottom) Following densitometry, intensities of bands corresponding to phosphorylated proteins were divided by intensities of the corresponding total protein bands to correct for small differences in protein loading. Results (mean ± S.E.M.) for caudate-putamen (left in each figure) and nucleus accumbens (right in each figure) are expressed in comparison to the normalized control, which was defined as the group injected with saline vehicle.