Brain expression of pCREB in rats exposed to consummatory successive negative contrast.

A 32-to-4% sucrose devaluation leads to suppression of consummatory behavior relative to unshifted 4% sucrose controls. This is accompanied by an emotional response inducing memory consolidation. Expression levels of phosphorylated cyclic adenosine monophosphate response element-binding protein (pCREB, a marker of synaptic plasticity) were higher after the first devaluation session than after the second in prelimbic cortex, anterior cingulate cortex, and dorso-medial striatum. The central nucleus of the amygdala showed a tendency to differential pCREB expression. This evidence contributes to identifying the brain circuit for one form of traumatic memory involving reward loss.