1. Repression of contexual fear memory induced by isoflurane is accompanied by reduction in histone acetylation and rescued by sodium butyrate 
T. Zhong, Q.J. Qing, Y. Yang, W.Y. Zou, Z. Ye, J.Q. Yan, Q.L. Guo 
British Journal of Anaesthesia 
Volume 113, Issue 4, Pages (October 2014)
DOI: /bja/aeu184
Copyright © 2014 The Author(s) Terms and Conditions

2. Fig 1
(a) Timeline of experiment. (b) Freezing time of each group (n=14) during contexual fear conditioning (CFC) training and CFC testing the next day,** P<0.01 vs isoflurane (ISO)+vehicle group. Mean (sd) shown. (c) Freezing time of each group (n=12) during mock training and mock test in next day, were similar. Mean (sd) shown.
British Journal of Anaesthesia  , DOI: ( /bja/aeu184)
Copyright © 2014 The Author(s) Terms and Conditions

3. Fig 2
Comparison of histone acetylation and c-Fos expression by immunoblotting between the air-exposed group and isoflurane-exposed group when the mice were in home cage (HC, n=6), at 1 h after mock training (MT, n=6) and 1 h after CFC training (n=6). Acetylation levels were measured by the ratio of H3 acetylation/total H3 or ratio of H4 acetylation/total H4, c-Fos expression was measured by c-Fos/β-actin ratio. *P<0.05, **P<0.01 vs HC+air group; ##P<0.01 vs MT+air group; &&P<0.01 vs CFC+air group. Results were normalized against the HC+air group, mean (sd) shown.
British Journal of Anaesthesia  , DOI: ( /bja/aeu184)
Copyright © 2014 The Author(s) Terms and Conditions

4. Fig 3
Representative immunocytochemistry images of (a) H3K9 acetylation and (b) H3K14 acetylation in the CA1, CA3, and DG regions of each group (n=6) 1 h after CFC training. H3 acetylation in hippocampal neuronal nuclei is stained brown. (c) Relative OD value of H3K9 acetylation and (d) H3K14 acetylation in the CA1, CA3, and DG regions of each group 1 h after CFC training. The relative OD value of H3K14 acetylation in CA1 was reduced by exposure to isoflurane. Chronic systemic SB administration rescued isoflurane-induced reduction in H3K14 acetylation. *P<0.05 vs ISO+vehicle group. Results were normalized against the air+vehicle group, mean (sd) shown. (e) H3K9, H3K14 acetylation levels in the CA1 region via by immunoblotting 1 h after CFC training. H3K9, H3K14 acetylation, and total H3 immunoreactive densities are shown for each group (n=6). (f) Relative histone acetylation measured by the ratio of H3 acetylation/total H3, *P<0.05, **P<0.01 vs ISO+vehicle group. Results were normalized against the air+vehicle group, mean (sd) shown.
British Journal of Anaesthesia  , DOI: ( /bja/aeu184)
Copyright © 2014 The Author(s) Terms and Conditions

5. Fig 4
Representative immunocytochemistry images of (a) H4K5 acetylation and (b) H4K12 acetylation in the CA1, CA3 and DG regions of each group 1 h after CFC training. H4 acetylation in hippocampal neuronal nuclei were stained brown by DAB. (c) Relative OD values of H4K5 acetylation and (d) H4K12 acetylation in CA1, CA3, and DG regions of each group 1 h after CFC training. Relative OD values of H4K5 acetylation in CA1 and DG regions, and H4K12 acetylation in the CA1 region were reduced by exposure to isoflurane. Chronic systemic SB administration rescued isoflurane-induced reduction in H4K5 and H4K12 acetylation. *P<0.05 vs ISO+vehicle group. Results were normalized against the air+vehicle group, mean (sd) shown. (e) H4K5, H4K12 acetylation in the CA1 region via by immunoblotting 1 h after CFC training. H4K5, H4K12 acetylation, and total H4 immunoreactive densities are shown for each group (n=6). (f) Relative histone acetylation measured by the ratio of H4 acetylation/total H4, *P<0.05, **P<0.01 vs ISO+vehicle group. Results were normalized against the air+vehicle group, mean (sd) shown.
British Journal of Anaesthesia  , DOI: ( /bja/aeu184)
Copyright © 2014 The Author(s) Terms and Conditions

6. Fig 5
(a) Representative immunocytochemistry images of c-Fos in hippocampal region CA1, CA3, and DG of each group 1 h after CFC training. Hippocampal neuronal nuclei were stained purple with haematoxylin, nuclear c-Fos protein was stained brown. (b) c-Fos-positive cell counts. Mice exposed to isoflurane exhibited a reduction in c-Fos positive CA1 neurones 1 h after CFC training. Chronic systemic SB administration rescued isoflurane-induced reduction in c-Fos expression. No difference in c-Fos between the groups was observed in the CA3 and DG region. *P<0.05,**P<0.01 compared with the ISO+vehicle group. Mean (sd) shown. (c) c-Fos protein levels in CA1 determined via by immunoblotting 1 h after CFC training. c-Fos protein expression was measured by the ratio of c-Fos/β-actin, *P<0.05,**P<0.01 vs ISO+vehicle group (n=6). Results were normalized against air+vehicle group, mean (sd) shown.
British Journal of Anaesthesia  , DOI: ( /bja/aeu184)
Copyright © 2014 The Author(s) Terms and Conditions