Figure 4: Blood glucose (a) and plasma insulin levels (b) in response to a 30-minutes intravenous glucose infusion after 1 day of sleep restriction (closed triangles, ), sleep disturbance (closed circles, ), or control (open circles, ). The horizontal grey bars at the bottom of the graphs represent the 30 minutes of 15% glucose infusion. Data are average values ± SEM. Asterisks indicate a significant difference between sleep restricted rats and controls ( P < .05) and # indicates a significant difference between sleep disturbed rats and controls ( P < .05).