Fig. 3

Immunohistochemical analysis of NF-IL6 in the SFO and neighboring choroid plexus (a–e) and in the cortex (f–j) 4.5 h after LPS or vehicle administration (n = 5). In the hypothalamus, there was no nuclear NF-IL6 immunoreactivity in the SHAM group (b) while all septic groups (c–e) showed strong intranuclear NF-IL6 signals. Vagus nerve stimulation (e) significantly reduced the percentage of nuclear NF-IL6 signals compared to the LPS + SHAM group (P < 0.01) and the LPS + VGX group (P < 0.01) (k). In the cortex, hardly any nuclear NF-IL6 signals could be detected after 4.5 h (g–j). The scale bar in picture B represents 25 μm and applies to pictures B–E and the scale bar in picture G represents 50 μm and applies to pictures g–j. Cell nuclei are stained in blue and NF-IL6 in red. Data are given as means ± SEM. Significance is given as: * compared to SHAM; *P < 0.05; **P < 0.01; ***P < 0.001; # compared as indicated; ^# P < 0.05; ^## P < 0.01; ^### P < 0.001; NF-IL6 nuclear factor IL-6, SFO subfornical organ, LPS lipopolysaccharide, SHAM sham surgery, VGX bilateral vagotomy, VGX + VNS bilateral vagotomy and distal vagus nerve stimulation