Short Term Effect of Enriched Environment on c-Fos Protein Expression, The

Environmental enrichment (EE) has been intensively used to study activity-dependent plasticity in the nervous system. Studies have shown the effects of EE from functional to anatomical level within different brain regions. c-Fos is a transcriptional factor encoded by the immediate-early gene (IEG) Fos in mice, and it is one of the most widely used markers for neuronal activation in the central nervous system. In this study, we explore the short term effect (3hrs) of EE on c-Fos expression in juvenile mice brain (P20-27) compared to standard environment (SE). Immunohistochemical assay followed by diaminobenzidine (DAB) staining was employed to visualize and quantify the c-Fos expressing cell population under microscope. Our result shows a significant increase on the number of cells expressing c-Fos in several brain regions of mice exposed to EE, including motor cortex, piriform cortex, somatosensory cortex, hippocampus, thalamus and hypothalamus, compared with control mice. This suggests an elevated activity of these brain regions in mice exposed to EE, and future investigation will be needed.