Pharmacogenetic activation of rostromedial tegmental nucleus (RMTg) neurons increased non-rapid eye movement (NREM) sleep in rats.

(A, B) Sleep–wake quantities following saline and clozapine-N-oxide (CNO) injection, including average hourly (A) and total sleep–wake amounts (B) during the post-injection period (09:00–16:00 hours). (C–G) Sleep–wake architecture during the post-injection period (09:00–16:00 hours), including conversions between S (NREM sleep), W (wakefulness), and R (REM sleep) stages (C), episode numbers of sleep–wake stages (D), number of NREM and REM sleep bouts with different duration (E, G), and mean duration of sleep–wake stages (F). (H, I) Average slow-wave activity (SWA) of NREM sleep (H) and electroencephalogram (EEG) power of REM sleep in the frequency range of 6–10 Hz (I) during the post-injection period (09:00–16:00 hours) following saline and CNO injection. *p < 0.05, **p < 0.01 versus saline by paired t tests. CNO (0.3 mg/kg) was given by intraperitoneal (IP) injection at 09:00 hours (n = 9). The horizontal open and filled bars on the x-axes indicate the 12-hour light period and the 12-hour dark period, respectively. Underlying data can be found in S1 Data.