Figure 3
Increases in inflammatory and neural activity in the vHPC of vulnerable rats. (a) Representative immunohistochemistry images for Iba1 showing regions analyzed in bar graphs. (b) Iba1 expression was increased in the vHPC of SL/vulnerable rats relative to control and LL/resilient rats (n=7; F2,19=20.78, P<0.0001). (c) There was no difference in expression of Iba1 in the dorsal hippocampus between any of the groups (n=8 per group). (d) Measurement of FITC extravasation showed FITC was significantly increased up to 7 μm away from blood vessels in SL/vulnerable rats relative to control and LL/resilient rats (main effect of group, F2,112=25.83, P=0.0001; and main effect of distance, F6,112=4.35, P=0.001). (e) There were no significant main effect of group between any groups in the dHPC but there was a significant main effect of distance (F6,119=10.76, P=0.0001). (f) Plasma S100β was negatively correlated with defeat latencies (n=11, r=−0.75, P=0.0009). (g and h) The long-term neuronal activity marker FosB/ΔFosB was increased in the vHPC CA1 region of SL/vulnerable rats (n=5) relative to control (n=8) and resilient LL rats (n=5; F2,15=18.16, P<0.0001). (i) There was no difference in FosB/ΔFosB expression in the vHPC CA3 region. (j and k) There was no difference in FosB/ΔFosB expression between groups in the CA1 (n=8 per group) or CA3 region (control n=7, SL n=8, LL n=8) of the dHPC (P>0.05). The letter 'a' denotes significant effect of distance and 'b' denotes significant group effect with SL/vulnerable higher than other groups. Data represent mean+s.e.m. *P<0.05. dHPC, dorsal hippocampus; FITC, fluorescein isothiocyanate; LL, long latency; SL, short latency; vHPC, ventral hippocampus.
