Striatal expression of hnPENK. (A) Pseudocolor autoradiographic phosphorescence image of a coronal brain sections at the level of the anterior (left) and posterior (right) striatum hybridized with a probe for hnPENK from a rat in the water cues group (top) and the Ensure cues group (bottom). (B) Graphical representation of semiquantitative measurements of in situ hybridization for hnPENK in striatal regions. Ensure cues increased the expression of hnPENK in the nucleus accumbens core and ventrolateral and medial regions, but not in the nucleus accumbens shell and dorsolateral regions (*p < 0.05). (C) Graphical representation of the results of extrastriatal immediate early gene expression and striatal hnPENK expression correlation analyses in both the water cues and the Ensure cues groups. Correlations that were significant are color-coded by the range in which their Pearson product moment (r) value lies (see key). Correlations that are not significant are shaded light gray. For abbreviations, see legend to Figure 1.