Figure 5.

Anxiolytic effects of pharmacological modulation of serotonergic activity in anxious SNI rats. (a) Citalopram treatment alleviated anxiety-like behaviors of SNI animals. Sub-chronic administration of Citalopram (10 mg/kg, i.p., q.d., for 15 days) effectively reversed the reductions of open arm entries (top left) and open arm time (top right) in EPM in SNI rats, as well as the number of entries into the central area in open field (bottom left). No difference in the total distance travelled in open field among the three groups (bottom right). Sham group: n = 8, SNI-Veh group: n = 9, SNI-CIT group: n = 8. (b) Intra mPFC perfusion of serotonin (7.7 μg in 0.65 μL) reversed anxiety-like behaviors of SNI animals. SNI rats received serotonin infusion which significantly increased open arm entries (left) and open arm time (right) in EPM, both values being comparable with those of sham group. Sham group: n = 10, SNI-Veh group: n = 9, SNI-5HT group: n = 10. Data are represented as mean ± s.e.m. *P < 0.05, **P < 0.01, ***P < 0.001, Sham versus SNI-Veh, SNI-Veh versus SNI-CIT or SNI-5HT, by one-way ANOVA followed by Bonferroni's multiple comparisons test.

CIT: citalopram; Veh: vehicle; 5HT: serotonin; SNI: spare nerve injury.