Fig 1.
Sleep architecture in Wistar and msP.
(A) Representative hypnograms for Wistar and msP rats. (B-C) Distribution of wake, NREM sleep, and REM sleep amount (mean ± std) in the 24h (B) and during light and dark periods (C). (D) Twenty-four-hour time course of minutes spent in each state (mean ± SEM). Grey areas indicate the dark cycle, from 8:00 pm to 8:00am. (E) Distribution of the number of episodes in the light, L, and dark, D, phase (mean ± std). (F) Number of sleep attempts during the 24 hours. (G) Sleep fragmentation index computed as the number of wakefulness episodes/ total sleep time. (H) Number of transitions between stages. (I) Percentage of time spent in active or quiet wake during the light, L, and dark, D, period. Empty circles represent individual rats (Wistar n = 9, msP n = 9). * p < 0.05, ** p < 0.01.
Fig 2.
EEG power spectrum of frontal channels. (A) Power spectrum of EEG (mean ± std) during NREM sleep and values of SWA (0.5-4 Hz), NREM sleep sigma (12-15 Hz) and beta (15-30 Hz) power across 24 hours. (B) Power spectrum of EEG during REM sleep and values of REM sleep low theta (5-8 Hz), high theta (8-12 Hz) and beta power across 24 hours. (C) Power spectrum of EEG during wake and values of high theta, beta, and theta/beta ratio power across 24 hours during waking epochs. Values are mean ± std. Empty circles represent values for individual rats. * p < 0.05; ** p < 0.01; *** p < 0.001; **** p < 0.0001.
Fig 3.
EEG power spectrum of parietal channels.
(A) Power spectrum of EEG (mean ± std) during NREM sleep and values of SWA (0.5-4 Hz, p = 0.37 unpaired t-test), NREM sleep sigma (12-15 Hz, p = 0.0001) and beta (15-30 Hz, p < 0.0001) power across 24 hours. (B) Power spectrum of EEG during REM sleep and values of REM sleep low theta (5-8 Hz, p = 0.14, Mann-Whitney test), high theta (8-12 Hz p = 0.52, unpaired t-test) and beta (p = 0.0036, unpaired t-test) power across 24 hours. (C) Power spectrum of EEG during wake and values of high theta (8-12 Hz, p = 0.32, Mann-Whitney test), beta (p = 0.0014, unpaired t-test) and theta/beta ratio power across 24 hours during waking epochs (p = 0.0037, Mann-Whitney test). Values are mean ± std. Empty circles represent individual rats. * p < 0.05; ** p < 0.01; *** p < 0.001; **** p < 0.0001.
Fig 4.
(A) Twenty-four-hour time course of SWA (mean±sem), two-way ANOVA interaction rat line x time p < 0.0001, uncorrected Fisher LSD post hoc test p = 0.02. The grey area indicates 12hrs of lights off. (B) SWA change during the light period (1st hour – 12th hour of light period, unpaired t-test p = 0.0042), mean±std. (C) SWA during the dark period (1st hour – 12th hour of dark period, unpaired t-test p = 0.0154), mean±std. (D) Representative EEG signal (band-pass filtered 0.5-4 Hz) during early and late sleep for Wistar (upper part) and msP (lower part). (E) Values of slow wave amplitude during early and late sleep. (F) Slope of slow waves during early and late sleep. (G) Duration of slow waves. (H) Frequency of slow waves during early and late sleep. (I) Incidence of slow waves. Columns indicate mean ± SEM. Empty circles are single rats. Data in E-I were analyzed with repeated measures two-way ANOVA followed by Sidak’s multiple comparison test, see Supplementary Table 1 for detailed statistical results. * p < 0.05, ** p < 0.01, **** p < 0.0001.
Fig 5.
(A) Twenty-four-hour time course of NREM sigma power (mean±SEM). Two-way ANOVA, effect of rat line p < 0.0001, interaction time x rat line p < 0.0001. (B) NREM sigma change during the light period (mean at 12hrs – mean in the 1st hour), unpaired t-test p = 0.021. (C) Representative trace of EEG signal from Wistar rat (raw top, filtered12-15 Hz middle) and spectrogram (bottom). (D) Values of spindle amplitude during early and late sleep. (E) Incidence of sleep spindles (spindles/min) in early and late sleep. (F) Length of -spindles increases in Wistar rats from early to late sleep, but not in msP. (G) Frequency of spindles peaks around 14 Hz in Wistars, at 13.3 Hz in msP. (H) Number of oscillations in each spindle is higher in Wistar rats relative to msP. Wistar (grey); msP (red). Empty circles represent individual rats. Sidak’s multiple comparisons test. * p < 0.05; ** p < 0.01; *** p < 0.001; **** p < 0.0001.