Fig. 4: Interactions between ventral hippocampal SWRs and amygdalar LFP power related to SD stress.
From: Hippocampal sharp wave ripples underlie stress susceptibility in male mice
a Simultaneous recordings of LFP signals from the vHC and the AMY (histological confirmation shown in the left panel). The same results were obtained from 5 mice with electrodes implanted in the amygdala. b (Top) Changes in the ventral hippocampal SWR rate (bin = 2 min) in an SD mouse. The SD period was removed from the analysis. (Bottom) The corresponding amygdalar LFP power spectrum normalized to the average power during the prestress period in each frequency band. c (Left) Amygdalar LFP power in the 30-min poststress period normalized by the 0–30-min prestress, plotted against each frequency band (n = 5 mice). The asterisk indicates the 30–90 Hz band, in which there was a significant LFP power change between the two periods (t4 = 5.47, *P = 0.0055, two-sided paired t test). The data are the mean ± SEM. (Right) Correlations between the ventral hippocampal SWR rate changes and amygdalar LFP power changes in the poststress period. d (Left) Ventral hippocampal SWR-triggered AMY LFP power spectra in the prestress and poststress periods in an SD mouse. (Right) Average ventral hippocampal SWR-triggered amygdalar LFP power from all recordings (n = 5 mice) plotted against each frequency band. The asterisk indicates a significant increase in power in the 30–90 Hz band relative to 100%, as indicated by paired t test (P < 0.05). e LFP signals were recorded from the AMY in AAV-shCalb1-injected mice or mice that were bilaterally injected with muscimol into the vHC after the SD period. f SI ratios of non-SD mice (uninjected; n = 11 mice), SD mice (uninjected; n = 31 mice), AAV-shCalb1-injected mice (n = 8 mice, and SD mice injected with muscimol into the vHC (n = 10 mice). Non-SD versus SD, Z = 3.23, **P = 0.0036; SD versus shCalb1, Z = 3.15, **P = 0.0048; SD versus muscimol, Z = 3.26, **P = 0.0022, two-sided Mann–Whitney U test followed by Bonferroni correction. g SD-induced changes in the average AMY power in the 30–90 Hz band in uninjected SD mice (red, n = 5 mice), AAV-shCalb1-injected mice (cyan, n = 5 mice), and mice injected with muscimol into the vHC (purple, n = 4 mice). *P < 0.05, 0–30-min prestress versus 0–30-min poststress periods in the SD mice, two-sided Mann–Whitney U test followed by Bonferroni correction. The data are the mean ± SEM.
