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. 2016 Apr 15;5:e12917. doi: 10.7554/eLife.12917

Figure 4. Hippocampal neurosteroid E2 levels increase during KA seizures.

(A) Mean ± SEM percent baseline (BL) E2 before and after KA showing that KA-induced seizures increased hippocampal E2 concentration (**p<0.001 relative to BL, post-hoc paired t-tests). (B-D) Time in Racine 1–5 seizures (left) was used to classify rats into those experiencing mild (<30 min, B), moderate (30–90 min, C), or severe (>90 min, D) seizures, and E2 levels (right) were measured before and after KA. Rats with mild seizures (B) showed a small delayed increase in hippocampal E2, whereas rats with moderate seizures (C) showed a large (x3 BL) increase within 30 min (*p<0.05, **<0.01 relative to BL, paired post-hoc t-tests). E2 levels did not change in rats with the most severe seizures (D). (E) Mean ± SEM E2 concentrations during baseline (BL) and after KA injection (KA) for rats with mild/moderate vs. severe seizures shows that basal E2 was significantly higher in rats in which KA produced severe seizures (*p<0.05, t-test), whereas E2 increased from low to high levels in rats in which KA produced mild/moderate seizures (*p<0.05, t-test).

DOI: http://dx.doi.org/10.7554/eLife.12917.009

Figure 4.

Figure 4—figure supplement 1. Placements of microdialysis probes.

Figure 4—figure supplement 1.

(A) A representative photomicrograph showing a microdialysis probe track extending into the hippocampus. Damage from the probe extended into the dentate gyrus due to the glue plug (~0.2 mm) at the tip of the probe. Scale = 1 mm. (B) The locations of dialysis probe active membranes (yellow boxes, 1 mm length) for rats used in experiments to investigate seizure-induced changes in hippocampal E2 levels. The numbers in the center indicate rostral-caudal coordinates from bregma (Paxinos and Watson, 2004). There were no differences in basal E2 concentration due to rostral-caudal probe placement (p=0.51, one-way ANOVA).
DOI: http://dx.doi.org/10.7554/eLife.12917.010
Figure 4—figure supplement 2. No difference in seizure-induced changes in hippocampal E2 by sex or hemisphere.

Figure 4—figure supplement 2.

The seizure-induced increase in hippocampal E2 was similar in both males (A) and females (B) (p=0.35, two-way mixed ANOVA) and in the left (C) and right (D) hippocampus (p=0.63, two-way mixed ANOVA). BL = baseline.
DOI: http://dx.doi.org/10.7554/eLife.12917.011