Fig. 6.
Recovery sleep is delayed in propofol-fed flies after sleep deprivation (SD). (A) Representative experiment showing mean ± SEM time sleeping in minutes per hour plotted relative to zeitgeber time (ZT) in flies fed 1.0 mM propofol (PPF, n = 15) or vehicle (VEH, n = 16), indicated by the red horizontal bar, during the 6-h morning period after a 10 h SD (gray horizontal bar) in two other groups (VEH + SD, n = 16, and PPF + SD, n = 7). (B) Mean ± SEM net changes in sleep (minutes per 12 h) are reported for sleep-deprived flies for the day immediately after SD (day 1) and the next day (day 2). **P < 0.0001, *P < 0.03, one-sample t test, Bonferroni corrected; n = 48 VEH flies and 30 PPF flies across three independent experiments (see text for details). (C) Survival was monitored during the 6-h propofol treatment period (from ZT 0 to 6) and for up to 5 to 6 days afterward. Survival was plotted using the Kaplan–Meier estimator. Propofol treatment did not significantly alter survival in nondeprived flies (handled control, left panel, P = 0.08 log-rank test, n = 46 flies each group) but reduced survival in sleep-deprived flies (P < 0.0001, log-rank test, n = 48, 44 flies for VEH and PPF groups, respectively). (D) Mean ± SEM propofol concentration (plotted on a logarithmic scale) in fly heads is shown for propofol-fed flies (1.0 mM) that were sleep deprived as in A and for nondeprived controls (Ctrl); N = 3 replicates containing five flies each. (E) Arousal responses after strong mechanical stimuli are shown for indicated groups during propofol or vehicle treatment (ZT 4 to 6 refers to stimulus times), 10 to 12 h after treatment (night), and 24 h after vehicle or drug treatment (24-h recovery). *P < 0.04, Mann–Whitney; percent flies responding are reported as a proportion of sleeping flies from n = 64 and 48 VEH and propofol controls, respectively, and 63 and 33 VEH and propofol-fed flies, respectively, that were subjected to SD across four independent replicates.