Pathological changes in neuronal dendrites and presynaptic terminals of METH-treated WT and HIV-1 gp120tg mice after seven months of drug abstinence. At 10–11 months of age and seven months of abstinence from METH, gp120tg and WT animals were sacrificed and brain tissues harvested. Immunostaining of sagittal brain sections for neuronal markers and quantitative microscopic analysis was performed as described in the methods section. Deconvolved images of MAP-2 and Synaptophysin (Syp) staining on brain sections from hippocampus CA1 region, molecular layer (A), and fronto-parietal cortex, layer III (B). Scale bar: 40 µm. (C) Percentage of neuropil positive for neuronal MAP-2 and Syp estimated by deconvolution microscopy in hippocampus and fronto-parietal cortex of METH- or SAL-treated gp120tg and WT mice. Graphs show mean ± SEM; * p ≤ 0.0007 (ANOVA and Fisher’s PLSD post hoc test, n = 4–6 animals per group; n.s., not significant).