Fig. 2.

Effects of inescapable tail shock (IS) on tph2 mRNA expression. (a) Representative bregma levels of the neuroanatomical analysis atlas for tph2 mRNA expression in all anatomical subdivisions of the serotonergic dorsal raphe nucleus (DR) studied in an adult, male rat brain. (b) Mean ± SEM tph2 mRNA expression throughout the rostrocaudal extent of the entire DR (subdivisions averaged), in Experiment 1. (c) Mean ± SEM tph2 mRNA expression throughout the rostrocaudal extent of the dorsal raphe nucleus, dorsal part (DRD), including the rostral aspect (rDRD) and the caudal aspect (dorsomedial DR, cDRD) in Experiment 1. (d) Overall tph2 mRNA expression in the entire DR (subdivisions and rostrocaudal levels averaged) after exposure to home cage control conditions (HC) or IS. All rats were euthanized 4 h after the onset of IS (IS, n = 8), including unstressed control rats (HC, n = 8). (e) Overall tph2 mRNA expression in the dorsomedial DR (cDRD; rostrocaudal levels averaged). (f) Representative photomicrographs of tph2 mRNA expression at bregma level–8.000 mm, measured using in situ hybridization histochemistry. Post hoc comparisons were made using Student's t-tests. *p < .05, IS vs HC. Post hoc testing was not conducted at a specific rostrocaudal level (7 through −6) when 1 or more groups contained less than half of the full sample size, indicated by the right y-axis. Rostrocaudal levels 7 = −7.580 mm, 6 = −7.664 mm, 5 = −7.748 mm, 4 = −7.832 mm, 3 = −7.916 mm, 2 = −8.000 mm, 1 = −8.084 mm, 0 = −8.168 mm, −1 = −8.252 mm, −2 = −8.336 mm, −3 = −8.420 mm, −4 = −8.504 mm, −5 = −8.588 mm, −6 = −8.672 mm from bregma. Scale bar: 1 mm.