Figure 1. eB3 is required for defensive responses and activation of neurons in the amygdala.

(a) c-Fos expression (arrowheads indicated yellow cells) in neurons of the amygdala was markedly elicited after an EPM behavioural trial from P9 to P20. Blue: neurotrace to stain BLA cell layer at P9–P20. Scale bar, 100 μm. (b) Quantification of c-Fos-positive cells (percentage of total neurotrace-positive cells) in BLA or lateral amygdala (LA) from P9 to P20 following an EPM or TMT behavioural trial. n=6 mice for each group. (c) Representative animal track of EPM, and representative images showing the c-Fos-positive cells in amygdala of Efnb3^+/+, Efnb3^−/− and Efnb3^lacZ/lacZ mutant mice following EPM trial at P16. Scale bars, 100 μm. (d) Efnb3^−/−, but not Efnb3^lacZ/lacZ, mutant mice showed a longer time and a higher probability of open-arm entry than Efnb3^+/+ at P16, P20 and P42. The experiments were triplicated independently. n values of mice used are indicated above group bars. *P<0.05; **P<0.01; ***P<0.001, one-way ANOVA. (e) Quantification of the cells with c-Fos expression at Efnb3^+/+, Efnb3^−/− and Efnb3^lacZ/lacZ mutant in BLA, LA, CA1 and DG following an EPM or TMT trial. n values of mice are indicated above group bars. *P<0.05; ***P<0.001, one-way ANOVA.