Article Figures & Data
Figures
- Figure 1.
Detection of SWDs during awake–sleep stages in PV-ArchT mice. A, Left, Schematic representation of PV-tTA::tetO-ArchT transgenic mice fed with normal food from birth; right, a timeline of ArchT expression and EEG/EMG recordings. B, Types of epileptiform discharges in PV-ArchT mice. C, Example of EEG recording on P120. From top to bottom, Cortical EEG (red and blue traces illustrate typical SWDs and other epileptiform discharges, respectively), EEG spectrogram, EMG, hypnogram, and powers of the delta, theta, and sigma bands.
- Figure 2.
PV-ArchT mice exhibited SWDs during both the awake and sleep stages. A, Dot plots show an increase in the number of SWDs with age during wakefulness, NREM sleep, and REM sleep (one-way ANOVA, awake, n = 4 mice; F(3,12) = 3.82; p = 0.04; NREM sleep, n = 4 mice; F(3,12) = 6.26; p = 0.008; REM sleep, n = 4 mice; F(3,12) = 2.12; p = 0.15). Repeated-measure ANOVA followed by the Tukey–Kramer post hoc test, and the results of statistical tests are shown in Table 2. Data were recorded for 2–4 h for each mouse. B, Line plots on P120 show no changes in the frequency of SWDs between the dark and light phases (one-way ANOVA; awake, n = 5 mice; F(7,32) = 0.92; p = 0.50; NREM sleep, n = 5 mice; F(7,32) = 1.05; p = 0.41; REM sleep, n = 5 mice; F(7,32) = 0.83; p = 0.57). C, Total duration of the awake, NREM, and REM sleep stages; data were recorded in 24 h with a 12 h light/dark cycle (two-way ANOVA; awake, n = 4 mice; F(7,48) = 1.43; p = 0.22; NREM sleep, n = 4 mice; F(7,48) = 0.69; p = 0.68; REM sleep, n = 4 mice; F(7,48) = 0.37; p = 0.92). PV-ArchT mice fed with DOX-containing food from birth were used as controls.
- Figure 3.
Relationship between sleep spindle alteration and SWD development in PV-ArchT mice. A, Method for detecting sleep spindles in PV-ArchT (left) and control (right, PV-ArchT mice fed with DOX-containing food from birth) mice. From top to bottom, Raw EEG data recording, filtered sigma signals, wavelet analysis, and spindle power. The red lines represent the threshold value. Red-shaded areas indicate sleep spindle events. B, Summary graphs from left to right showing the sleep spindle patterns (density, duration, and power, respectively), comparing PV-ArchT mice (n = 5 mice for each group) with control mice (n = 3 mice for each group; PV-ArchT mice fed with DOX-containing food all life were used as controls). The results of statistical tests are shown in Table 3. C, Summary graphs from left to right show the number of SWDs/h and the sleep spindle patterns (density, duration, and power) before and after ethosuximide injection (n = 5 mice).
- Figure 4.
Temporal sequence between the SWD development and sleep spindle patterns in PV-ArchT mice. A, Left, Schematic representation of PV-tTA::tetO-ArchT transgenic mice fed with DOX-containing food. Right, A timeline of ArchT expression and EEG/EMG recordings. B, Dot plots showing the development of other epileptiform discharges during the awake, NREM, and REM stages (one-way ANOVA; awake, n = 4 mice; F(4,15) = 5.96; p = 0.004; NREM sleep, n = 4 mice; F(4,15) = 13.7; p < 0.001). Repeated-measure ANOVA followed by the Tukey–Kramer post hoc test, and the results of statistical tests are shown in Table 4. C, Dot plots showing the development of typical SWDs during the awake, NREM, and REM stages (one-way ANOVA; awake, n = 4 mice; F(4,15) = 10.2; p = 0.0003; NREM sleep, n = 4 mice; F(4,15) = 34.2; p < 0.001; REM sleep, n = 4 mice; F(4,15) = 37.3; p < 0.001). Repeated-measure ANOVA followed by the Tukey–Kramer post hoc test, and the results of statistical tests are shown in Table 5. D, Dot plots showing changes in sleep spindle density and duration (one-way ANOVA; density, n = 4 mice; F(4,15) = 49.8; p < 0.001; duration, n = 3 mice; F(4,15) = 1.53; p = 0.24). Repeated-measure ANOVA followed by the Tukey–Kramer post hoc test, and the results of statistical tests are shown in Table 6.
- Figure 5.
Drug-induced SWDs are associated with a reduction in sleep spindle density. A, Timeline illustrating the administration of GBL (100 mg/kg) to wild-type mice. B, Example of an EEG recording before (left) and after (right) GBL injection. From top to bottom, Cortical EEG, EEG spectrogram, and EMG. Red traces indicate SWDs. C, Summary graphs from left to right show the number of SWDs/h and the sleep spindle patterns (density, duration, and power) before and after GBL administration (n = 4 mice).
- Figure 6.
Temporal relationship between sleep spindle and SWDs in the GBL model of absence seizure. A, Timeline illustrating the administration of GBL (50 mg/kg) to wild-type mice. B, Summary graphs from left to right show the number of SWDs/h and the sleep spindle patterns (density, duration, and power) before and after GBL administration (n = 4 mice). C, The panels illustrate the daily protocols for caffeine and GBL injections. D, Summary graphs from left to right show the time course of NREM sleep duration per hour (one-way ANOVA from 11:00 to 13:00, F(2,9) = 12.2; p = 0.002) and sleep spindle patterns (density, duration, and power) on Days 0, 3, and 4 (one-way ANOVA; density, F(2,13) = 20.3; p = 0.00009; duration, F(2,13) = 4.45; p = 0.33; power, F(2,13) = 0.12; p = 0.89). Note that, for Days 0 and 3, data from NREM sleep between 9:00 and 13:00 were used for analysis, whereas for Day 4, data from NREM sleep between 11:00 and 13:00 were used for analysis. Repeated-measure ANOVA followed by the Tukey–Kramer post hoc test, and the results of statistical tests are shown in Tables 7 and 8. E, Left, Example of an EEG recording after GBL injection. From top to bottom, Cortical EEG, EEG spectrogram, and EMG. Red traces indicate SWDs. Right, Dot plot showing the number of SWDs before and after GBL injection (n = 6 mice).
Tables
SWDs (in PV-ArchT mouse) Sleep spindle Detection methods Visually Automated Shape SWDs Waxing and waning Power 7.3 ± 1.0 mV2
background, 3.5 ± 0.7 mV2
3.9 ± 0.3 mV2 Duration 0.5–10 s 0.5–1.5 s Occurrence During wakefulness, NREM sleep, and REM sleep Only during NREM sleep Frequency 7–10 Hz 10–16 Hz SWDs, spike-and-wave discharges; PV-ArchT, parvalbumin-tetracycline transactivator; NREM, nonrapid eye movement; REM, rapid eye movement.
- Table 2.
Results of Tukey–Kramer post hoc test for the number of SWDs per hour with age during awake and NREM sleep for the data in Figure 2A
Awake (n = 4 mice) NREM (n = 4 mice) P60 P90 0.50 0.50 P120 0.01* 0.03* P150 <0.001*** 0.01* P90 P60 – – P120 0.10 0.30 P150 0.003** 0.10 P120 P60 – – P90 – – P150 0.18 0.1 The bold values indicate statistically significant p values.
*p ≤ 0.05, **p ≤ 0.01, ***p ≤ 0.001.
- Table 3.
Results of the average sleep spindle patterns (density, duration, and power, respectively), with age in PV-ArchT and control mice for the data in Figure 3B
Density Duration Power P60 6.44 ± 0.55 vs 11.9 ± 1.84 0.39 ± 0.02 vs 0.37 ± 0.002 3.39 ± 0.42 vs 3 ± 1.03 p = 0.01** p = 0.33 p = 0.68 P90 6.20 ± 0.27 vs 12.0 ± 1.97 0.43 ± 0.03 vs 0.38 ± 0.03 3.77 ± 0.38 vs 3.13 ± 0.82 p = 0.01** p = 0.24 p = 0.44 P120 4.94 ± 0.33 vs 10.9 ± 2.26 0.36 ± 0.009 vs 0.35 ± 0.007 3.72 ± 0.22 vs 2.76 ± 0.55 p = 0.01** p = 0.83 p = 0.13 Control mice are PV-ArchT mice fed with DOX-containing food from birth; n = 3 mice. PV-ArchT mice fed with normal food from birth; n = 5 mice.
The bold values indicate statistically significant p values.
**p ≤ 0.01.
- Table 4.
Results of Tukey–Kramer post hoc test the number of epileptiform discharges per hour during awake and NREM sleep for the data in Figure 4B
Awake (n = 4 mice) NREM (n = 4 mice) DOX Week 1 1.0 0.9 Week 2 1.0 0.2 Week 3 0.5 0.01** Week 6 0.01** <0.001*** Week 1 DOX - - Week 2 1.00 0.2 Week 3 0.5 0.02* Week 6 0.01** <0.001*** Week 2 DOX - - Week 1 - - Week 3 0.5 0.6 Week 6 0.01** Week 3 DOX - - Week 1 - - Week 2 - - Week 6 0.1 0.1 The bold values indicate statistically significant p values.
*p ≤ 0.05, **p ≤ 0.01, ***p ≤ 0.001.
- Table 5.
Results of the Tukey–Kramer post hoc test on the number of SWDs per hour during awake and NREM sleep for the data are in Figure 4C
Awake (n = 4 mice) NREM (n = 4 mice) REM (n = 4 mice) DOX Week 1 1.0 1.0 1.0 Week 2 1.0 0.004 1.0 Week 3 0.2 <0.001*** 1.0 Week 6 0.001*** <0.001*** <0.001*** Week 1 DOX - - - Week 2 1.0 0.004 1.0 Week 3 0.169 <0.001*** 1.0 Week 6 0.001*** <0.001*** <0.001*** Week 2 DOX - - - Week 1 - - - Week 3 0.169 0.027 1.0 Week 6 0.001*** <0.001*** <0.001*** Week 3 DOX - - - Week 1 - - - Week 2 - - - Week 6 0.10 0.18 <0.001*** The bold values indicate statistically significant p values.
***p ≤ 0.001.
- Table 6.
Results of Tukey–Kramer post hoc test for the changes in sleep spindle density for the data in Figure 4D
Density (n = 4 mice) DOX Week 1 0.87 Week 2 <0.001*** Week 3 <0.001*** Week 6 <0.001*** Week 1 DOX – Week 2 <0.001*** Week 3 <0.001*** Week 6 <0.001*** Week 2 DOX – Week 1 – Week 3 0.15 Week 6 0.10 Week 3 DOX – Week 1 – Week 2 – Week 6 0.99 The bold values indicate statistically significant p values.
***p ≤ 0.001.
- Table 7.
Results of Tukey–Kramer post hoc test for the changes in time course of NREM sleep duration per hour from 11:00 to 13:00 for the data in Figure 6D
NREM duration (n = 4 mice) Before caffeine (Day 0) After caffeine (Day 3) <0.008** Caffeine + GBL (Day 4) <0.004** After caffeine (Day 3) Before caffeine (Day 0) – Caffeine + GBL (Day 4) 0.88 The bold values indicate statistically significant p values.
**p ≤ 0.01.
- Table 8.
Results of Tukey–Kramer post hoc test for the changes in sleep spindle density on Days 0, 3, and 4 for the data in Figure 6D
Density Before caffeine (Day 0) After caffeine (Day 3) <0.001*** Caffeine + GBL (Day 4) <0.001*** After caffeine (Day 3) Before caffeine (Day 0) - Caffeine + GBL (Day 4) 0.32 Before/after caffeine (n = 6 mice), caffeine + GBL (n = 4 mice).
The bold values indicate statistically significant p values.
***p ≤ 0.001.
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