Effect of antenatal dexamethasone treatment on the total number of apoptotic cells in the pyramidal cell layer in the CA (A) and in the granule cell layer of the DG (B).

<p>Data are presented as mean ± SD. Apoptosis is significantly increased in the dex-treated group in both the CA area (E16, E18 and P0) and the DG (E18 and P0). Sal: saline-treatment (n = 8), dex: dexamethasone-treatment (n = 8), * p<0.05 (Two-Way ANOVA+Bonferroni).</p

Effect of antenatal dexamethasone treatment on the total number of proliferative cells in the subgranular zone of the DG.

<p>Data are presented as mean ± SD. At E18 and P0, the number of proliferative cells is decreased in the dex-treated group, while an increase is observed at P5 and P10. At the adult stage the number of proliferative cells are decreased in the dex-treated group. Sal: saline-treatment (n = 8), dex: dexamethasone-treatment (n = 8), * p<0.05 (Two-Way ANOVA+Bonferroni).</p

Effect of antenatal dexamethasone treatment on the volume (A, B) and total number of neurons (C, D) of the hippocampus.

<p>Data are presented as mean ± SD. Panel A and C show a significant decrease in volume of the CA at P5 and P10 and in total number of neurons in the CA area at E18 until P10 and an increase of number of neurons in the CA of the dex-treated group at adulthood. Panel B shows an increase in volume of the DG of the dex-treated group at P10. Panel D shows a significant increase in total number of neurons in the DG of the dex-treated group at P10 and P20. Sal: saline-treatment (n = 8), dex: dexamethasone-treatment (n = 8). * p<0.05 (Two-Way ANOVA+Bonferroni).</p

Summary of the effects of antenatal dex treatment on proliferation and apoptosis in the DG during hippocampal development.

<p>The results of the dex treated groups are presented as percentage of the control (100%).</p

Timed regulation of biological processes after eFS.

<p>Bar blackness indicates the peak effect of the process. P10: postnatal day 10, 1H: 1 hour post-eFS, 3D: 3 days post-eFS, 14D: 14 days post-eFS, 56D: 56 days post-eFS, Glu/Gln cycle: glutamate/glutamine cycle.</p

Validation of microarray results by qPCR analysis.

<p>Gene expression levels as determined by qPCR (Rn) in normothermic (NT) and hyperthermic (HT) animals compared to fold-change in expression of 5 genes as detected by microarray analysis (Rm). <i>P</i> < 0.05 was considered significant (one-tailed Student’s t-test). Indicated are mean ± standard error of the mean.</p

Expression of candidate genes mRNA related to structural reorganization.

<p>(A, C, E, G) Representative images of <i>Nrxn1</i>, <i>Dpysl3</i>, <i>Ptprd</i>, and <i>Slit2</i> gene expression in the hippocampus of NT (left panel) and HT (right panel) animals three days after eFS. (B, D, F, H) Comparison of <i>Nrxn1</i>, <i>Dpysl3</i>, <i>Ptprd</i>, and <i>Slit2</i> gene expression levels in subfields of the hippocampus in HT (<i>n</i> = 9, red bars) animals compared to NT (<i>n</i> = 9, blue bars) littermates. <i>Ptprd</i> is upregulated in the CA2 subfield of the hippocampus of HT animals, * indicates a significant difference of <i>P</i> = 0.0097, littermate-paired Student’s t-test. Bars represents mean ± standard error of the mean. Scalebars in panel A, C, E, and G: 500μm.</p

Hierarchical clustering analysis of mRNA expression after eFS.

<p>Hierarchical clustering analysis of differentially expressed genes (930) in all experimental littermate couples (1 hour, 3 and 14 days post-eFS). Rows depict differential expression levels per HT/NT littermate couple, per time-point after eFS. Clustering was performed based on gene and sample clustering using Pearson correlation on average linkage. Tree cluster, right from heat-map, shows hierarchical distance between samples from the different time points. Differential gene expression (log2(Fc) between HT/NT littermate couples is shown in the heatmap as upregulated (red), downregulated (green), or no change (white) according to colored-scale bar.</p

Hyperthermia induces upregulation of neurofilament protein-expression.

<p>(A) Neurofilament (NF) immunostaining in the hippocampus of a normothermic (NT) control animal, 14 days post-hyperthermia exposure. Square marks subfield enlargement; panel B. (B) Immunostaining for NF in the stratum lucidum of NT control animal (left panel) and in hyperthermia-exposed (HT) littermate (right panel). (C) Comparison of NF-based DAB staining in the stratum lucidum between NT and HT littermates. All HT (<i>n</i> = 10) animals showed increased DAB-staining in the stratum lucidum. Pair-wise comparison of DAB-staining intensities showed increased NF expression in HT animals compared to NT littermates (<i>n</i> = 10), Wilcoxon signed-rank test, * indicates a significance of <i>P</i> = 0.0049. Tukey-style box plots. Scalebars: 100 μm.</p