Figure 1

Analysis of expression changes from the microarray studies. Venn diagrams illustrate the changes identified by microarray analysis of naïve animals, and animals following 1 and 10 or 100 days of abstinence. (A) In the mPFC, 21,814 probes were detected as present. Of these, 1,461 were changed by greater than 1.4 fold with p < 0.05 (ANOVA) and can be split into three categories based on expression profile: changed between naïve and 1-day (793), naïve and 100-days (480) or both (188). (B) In the NAc, 19,015 probes were detected as present. Of these, 414 were changed by greater than 1.4 fold with p < 0.05 (ANOVA), and can be split into the same three categories: changed between naïve and 1-day (68), naïve and 10-days (314) or both (32). (C) The three categories of gene expression changes can be segregated into (1) changes that occur with cocaine self-administration (SA) that do not persist, (2) changes that occur with cocaine SA that do persist, and (3) changes that occur during abstinence. Small graphs indicate the expression profile of changes in each category, where the x-axis represents group (naïve, 1-day and 10- or 100-days abstinent) and the y-axis represents percent (%) of naïve expression. (D) When comparing the gene expression changed between the mPFC and NAc, a majority (97%) are unique to one brain region or the other. Only a small fraction (50) is changed in both brain regions.