Fig. 4.
Photostimulation of IL-PFC produces antidepressant and anxiolytic behavioral responses. (A) Timeline for behavioral testing, starting 1 d after laser stimulation. Both rAAV2-GFP and rAAV2-ChR2-eYFP animals received laser stimulation, with the rAAV-GFP serving as controls. Experiments included animals receiving either unilateral (Uni-stim) or bilateral (Bistim) optical stimulation. The results demonstrate that both uni- and bistim of rats infused with rAAV2-ChR2-eYFP produced an antidepressant effect in the FST (B) (F2,20 = 21.229, P < 0.01) and an anxiolytic effect in the NSFT (C) (F2,17 = 14.619, P < 0.01) compared with animals receiving rAAV2-GFP control virus and blue light stimulation. Optical stimulation of IL also produced a significant effect in the SPT (D), although only in animals receiving bilateral stimulation (F2,21 = 3.935, P = 0.037). The antidepressant effect of IL optical stimulation in the FST was still present 17 d after the stimulation (E); at this time point, the effect was more robust in the animals receiving bilateral stimulation (F2,20 = 35.313, P < 0.01). (F–H) In contrast to IL, bilateral stimulation of PrL had no significant effect in the FST (F) (t6 = 0.594, P = 0.574), NSFT (G) (t6 = 0.226, P = 0.829), or SPT (H) (t6 = 1.302, P = 0.241). Data are the mean ± SEM (n = 4–11 per group). *P < 0.05, **P < 0.01 compared with control animals; analysis of variance (one-way ANOVA with LSD post hoc test) or independent t test.