F, REM epochs. Left panel: JZL had no LY2510924 chemical information effect on REM delta power. Middle panel: JZL had no effect on REM theta power. Right panel: For REM gamma, there was an overall interaction (treatment x time of day jasp.12117 within photoperiod, F(24, 236.78) = 1.81, p = 0.014), a secondary interaction (treatment x photoperiod, F(4, 235.193) = 4.82, p = 0.001), a nested interaction (time of day within photoperiod, F(6, 217.40) = 15.30, p < 0.001), and main effects of both treatment (F(4, 96.44) = 14.58, p < 0.001) and photoperiod (F(1, 121.40) = 77.38, p < 0.001). There was an overall dose-dependent effect of JZL on REM gamma power, with reduced gamma following both 8.0 (t(80.55) = -2.97, p = 0.015) and 16.0 mg/kg doses (t(49.88) = -4.32, p < 0.001). The 8.0 mg/kg dose reduced REM gamma across all time points in the first 15 Hr following administration (ZT 00?5: t(113.90) -2.58, p 0.044), while the 16.0 mg/kg dose decreased gamma power for 18 Hr after administrationPLOS ONE | DOI:10.1371/journal.pone.0152473 March 31,35 /Endocannabinoid Signaling Regulates Sleep Stability(ZT 00?8: t(67.41) -3.12, p 0.011). Symbols/Bars represent mean EM for 3 hr time bins (N = 8). Grey background in graphs shows dark photoperiod. Asterisks denote significant difference from vehicle baseline. All injections administered at onset of LP (ZT 00:00). (PDF) S5 Fig. Direct Activation of CB1 with CP47,497 Attenuates Gamma Frequency Oscillations During Sleep. A-C, Average power spectra for order Ensartinib Epochs of different vigilance states across the entire DP (left hand) and LP (right hand). Solid lines denote means and shaded region around lines denotes SEM. A, Wake. B, NREM. C, REM. D-F, Change over the day in summated power in different frequency bandwidths from the power spectra: delta (left hand column), theta (middle column), and gamma (right hand column). D, Wake Epochs. Left panel: CP47 had no effect on wake delta power. Middle panel: For wake theta power, there was a significant overall interaction (drug x time of day within photoperiod, F(15, 180.83) = 9.73, p < 0.001) with a significant reduction in wake theta at only a single time point during the dark photoperiod (ZT 15?8: t(186.39) = -2.29, p = 0.047). Right panel: For wake gamma, there was a significant overall interaction (drug x time of day within photoperiod, F(15, 179.99) = 3.04, p < 0.001) with a main effect of photoperiod (F(1, 135.02) = 6.86, p = 0.010). However, there was not a difference at any specific time point between low j.jebo.2013.04.005 or high dose CP47 and vehicle. E, NREM Epochs. Left panel: For NREM delta there was an overall interaction (drug x time of day within photoperiod, F(15, 179.22) = 3.07, p < 0.001). However, there were no pair-wise differences at any time point between high or low dose CP47 and vehicle. Middle panel: For NREM theta power, there was an overall interaction (F(15, 180.85) = 2.79, p = 0.001) with main effect of photoperiod (F(1, 157.14) = 50.99, p < 0.001). However, there were no pair-wise difference between drug treatment conditions and vehicle. Right panel: For NREM gamma, there was an overall interaction (drug x time of day within photoperiod, F(15, 181.48) = 3.50, p < 0.001), secondary interaction (drug x photoperiod, F(2, 184.76) = 8.82, p < 0.001) with main effects of drug treatment (F(2, 175.98) = 7.13, p < 0.001) and photoperiod (F(1, 174.89) = 11.39, p = 0.001). Specifically, 1.0 mg/kg CP47 reduced NREM gamma power during the first 9 Hr of the dark photoperiod (ZT12-21: t(191.79) = -2.38, p = 0.037.F, REM epochs. Left panel: JZL had no effect on REM delta power. Middle panel: JZL had no effect on REM theta power. Right panel: For REM gamma, there was an overall interaction (treatment x time of day jasp.12117 within photoperiod, F(24, 236.78) = 1.81, p = 0.014), a secondary interaction (treatment x photoperiod, F(4, 235.193) = 4.82, p = 0.001), a nested interaction (time of day within photoperiod, F(6, 217.40) = 15.30, p < 0.001), and main effects of both treatment (F(4, 96.44) = 14.58, p < 0.001) and photoperiod (F(1, 121.40) = 77.38, p < 0.001). There was an overall dose-dependent effect of JZL on REM gamma power, with reduced gamma following both 8.0 (t(80.55) = -2.97, p = 0.015) and 16.0 mg/kg doses (t(49.88) = -4.32, p < 0.001). The 8.0 mg/kg dose reduced REM gamma across all time points in the first 15 Hr following administration (ZT 00?5: t(113.90) -2.58, p 0.044), while the 16.0 mg/kg dose decreased gamma power for 18 Hr after administrationPLOS ONE | DOI:10.1371/journal.pone.0152473 March 31,35 /Endocannabinoid Signaling Regulates Sleep Stability(ZT 00?8: t(67.41) -3.12, p 0.011). Symbols/Bars represent mean EM for 3 hr time bins (N = 8). Grey background in graphs shows dark photoperiod. Asterisks denote significant difference from vehicle baseline. All injections administered at onset of LP (ZT 00:00). (PDF) S5 Fig. Direct Activation of CB1 with CP47,497 Attenuates Gamma Frequency Oscillations During Sleep. A-C, Average power spectra for epochs of different vigilance states across the entire DP (left hand) and LP (right hand). Solid lines denote means and shaded region around lines denotes SEM. A, Wake. B, NREM. C, REM. D-F, Change over the day in summated power in different frequency bandwidths from the power spectra: delta (left hand column), theta (middle column), and gamma (right hand column). D, Wake Epochs. Left panel: CP47 had no effect on wake delta power. Middle panel: For wake theta power, there was a significant overall interaction (drug x time of day within photoperiod, F(15, 180.83) = 9.73, p < 0.001) with a significant reduction in wake theta at only a single time point during the dark photoperiod (ZT 15?8: t(186.39) = -2.29, p = 0.047). Right panel: For wake gamma, there was a significant overall interaction (drug x time of day within photoperiod, F(15, 179.99) = 3.04, p < 0.001) with a main effect of photoperiod (F(1, 135.02) = 6.86, p = 0.010). However, there was not a difference at any specific time point between low j.jebo.2013.04.005 or high dose CP47 and vehicle. E, NREM Epochs. Left panel: For NREM delta there was an overall interaction (drug x time of day within photoperiod, F(15, 179.22) = 3.07, p < 0.001). However, there were no pair-wise differences at any time point between high or low dose CP47 and vehicle. Middle panel: For NREM theta power, there was an overall interaction (F(15, 180.85) = 2.79, p = 0.001) with main effect of photoperiod (F(1, 157.14) = 50.99, p < 0.001). However, there were no pair-wise difference between drug treatment conditions and vehicle. Right panel: For NREM gamma, there was an overall interaction (drug x time of day within photoperiod, F(15, 181.48) = 3.50, p < 0.001), secondary interaction (drug x photoperiod, F(2, 184.76) = 8.82, p < 0.001) with main effects of drug treatment (F(2, 175.98) = 7.13, p < 0.001) and photoperiod (F(1, 174.89) = 11.39, p = 0.001). Specifically, 1.0 mg/kg CP47 reduced NREM gamma power during the first 9 Hr of the dark photoperiod (ZT12-21: t(191.79) = -2.38, p = 0.037.