Effects of CXCL12 and DAMGO on [35S]GTPγS incorporation in brain slices from pups and adult rats. Coronal brain sections were treated with different agonist concentrations as indicated in the graphs. Autoradiographs (both top and bottom panels) show images from brain slices treated with vehicle (a), CXCL12 (b), Morphine (c), or DAMGO (d). Analysis was performed in different brain areas as shown in the middle picture (from Paxinos and Watson Atlas; medial cortex, MC; lateral cortex, LC; and hippocampus (fields CA1, CA2, and CA3). Data are expressed as mean ± SEM of n=4 animals per group. Statistics for pups: basal vs CXCL12, 50 nM p<0.001; basal vs morphine, 10 μM, p<0.01; basal vs DAMGO, 10 μM, p<0.001 for each area reported in graph. Newman–Keuls Multiple comparison test after ANOVA. Statistics for adult rats: basal vs CXCL12, 50 nM, p>0.05; basal vs morphine, 10 μM; basal vs DAMGO, 10 μM, p<0.001, CXCL12 vs morphine, 10 μM, CXCL12 vs DAMGO, 10 μM, p<0.001 for each area reported in graph, Newman–Keuls multiple comparison test after ANOVA