Figure 5.

Disruption of mTOR signaling attenuates light-induced phase delaying but enhances light-induced phase advancing of the circadian core body temperature rhythm. A, B, Representative double-plotted actographs of core body temperature recordings. Initially, cannulated mice were entrained on a 12 h LD cycle and then transferred to total darkness. After ∼10 d under DD, mice were infused with DMSO vehicle or the mTOR inhibitor rapamycin (Rapa; 100 μm) 30 min before light exposure (100 lux, 15 min) at CT15 (A) or CT22 (red asterisks) (B). Animals free ran for 7–14 d and then received a second infusion of rapamycin or DMSO followed by light treatment. Regression lines approximate the phase-delaying (A) or phase-advancing (B) effect of light. C, Statistical representation of the early-night (CT15) and late-night (CT22) data sets. Of note, the light-evoked phase delay was significantly attenuated by rapamycin. However, the light-evoked phase advance was significantly enhanced by rapamycin. Numbers above the bars denote the number of animals examined for each condition.