Figure 5.

Age differences in c-fos mRNA activation by acute or subchronic nicotine treatment. Age differences were observed in the prefrontal cortex (a), ^**p⩽0.02, but there was no effect of nicotine treatment. Solid line brackets denote age effects and dashed brackets represent pretreatment effects. Acute and subchronic nicotine-induced c-fos activation in the basolateral amygdala (BLA) and nucleus accumbens shell (NAc) shell of adolescent rats (b and c), ⁺⁺p<0.01, whereas adults only show nicotine-induced activation of BLA after subchronic treatment (c), ⁺p<0.05. Schematic representation of brain regions and autoradiographic analysis of regional c-fos mRNA levels (d). The gray regions were analyzed for c-fos. n=4–11 per group.