Effects of Alternating EE on depolarization-associated c-fos expression.

<p><b>A</b>, Low magnification image of c-fos immunohistochemistry on a coronal section of the hippocampus. Dotted line in the enlarged box illustrates how the granule cell layer (GCL) was divided into outer GCL and inner GCL for quantification purposes. <b>B,C</b> Quantifications of c-fos expression in the <b>B</b>, Outer GCL and <b>C</b>, Inner GCL. Note that a positive effect of the <i>Complex</i> environment (I-CPX) was detectable in both the Inner GCL and Outer GCL, while the <i>Running disc</i> environment (I-RUN) had a negative effect in the Inner GCL only. Socially-housed mice in empty cages (SOC) also exhibited increased c-fos expression compared to isolated mice (IMP). See <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0086237#s3" target="_blank">Results</a> for further details. <b>D</b>, Rostral-caudal distribution of c-fos-expressing cells in the DG. The rostral and caudal tissue sections correspond to the dorsal and ventral hippocampus regions, respectively. Note that the pattern of c-fos expression across groups is virtually identical in both the rostral and caudal DG. Scale bar: 250 µm. DG = Dentate Gyri. GCL = Granule Cell Layer.