Fig. 6

Brain c-Fos expression in 5-HTT-deficient mice. a Experimental design for brain sampling. 5-HTT−/− and 5-HTT+/+ mice were either exposed to the Porsolt forced swim test (PS, Exposure) or were left undisturbed until sacrifice without any exposure to behavioral testing (No exposure). b Schematic diagram of the brain areas in which c-Fos expression was quantified (brain images were adapted with permission from ref. [83]). c Representative photomicrographs of c-Fos immunoreactivity on brain regions (cingulate cortex, Cg; paraventricular thalamus, PVT). d–n Number of c-Fos-positive cells (/mm²) in the brain areas: (d) cingulate cortex (Cg), e infralimbic cortex (IL), f nucleus accumbens shell (AcbSh), g dorsolateral septum (LSD), h lateral hypothalamus (LH), i paraventricular thalamus (PVT), j ventromedial hypothalamus (VMH), k dorsal dentate gyrus (dDG), l ventral dentate gyrsu (vDG), m CA3, and n CA1. Scale bar, 200 μm. Values are means ± SEM. Asterisks indicate statistically significant differences between 5-HTT−/− and 5-HTT+/+ mice (*p < 0.05 and **p < 0.01)