Fig. 6: Lithium pilocarpine induced behavioral effects in mice with genetic deletion of TrkB in neurons or in astrocytes.

TrkB^f/f-GFP-Veh, TrkB^f/f-GFP-Pilo, TrkB^f/f-GFAP-Cre-Pilo, and TrkB^f/f-CaMKII-Cre-Pilo mice were subjected to an open field (day 7 after pilocarpine treatment) and to a novel object location test (NOL, day 9 after pilocarpine treatment) assays. In the open field, a time spent in the center of the arena, b locomotor activity, and c parallel index were monitored for 30 min in all groups of mice. a Locomotor activity measurement indicated significant differences between groups (two-way ANOVA, group effect: F_(3,675) = 15.78, p < 0.001), post hoc analysis indicated that TrkB^f/f-GFP-Pilo mice were the only ones who were significantly different compared with TrkB^f/f-GFP-Veh mice (p < 0.001). b In the variable time spent in the center of the arena we identified a general significant effect from all groups treated with pilocarpine compared with TrkB^f/f-GFP-Veh mice (one-way ANOVA: F_(3,44) = 13.25, p < 0.001). c In the variable parallel index, we identified a general significant effect from all groups treated with pilocarpine compared with TrkB^f/f-GFP-Veh mice (one-way ANOVA: F_(3,44) = 6.27, p < 0.001). d In the NOL test, the percentage of time exploring the displaced object (new location, NL, 24 h after first exposure) and the unmoved object (old location, OL) was compared. Two-way ANOVA indicated a significant interaction effect groups × object location (F_(3,88) = 14.46, p < 0.001) and post hoc analysis indicated that only TrkB^f/f-GFP-Veh (p < 0.001) and TrkB^f/f-GFAP-Cre-Pilo (p < 0.05) mice showed significant preference for the displaced object. Bars represent mean ± SEM. Data were analyzed by two-way analysis (a, d) or one-way (b, c) of variance (ANOVA) with Bonferroni’s test as a post hoc. *p < 0.05 and ***p < 0.001 compared with vehicle controls. TrkB^f/f-GFP-Veh (n = 15), TrkB^f/f-GFP-Pilo (n = 16), TrkB^f/f-GFAP-Cre-Pilo (n = 8), and TrkB^f/f-CaMKII-Cre-Pilo (n = 10).