PMC

Correlation between SOL and DPG. SOL (3 continuous epochs to sleep) and DPG were correlated such that a greater change in DPG was associated with a shorter SOL in the ramelteon condition (B) compared to placebo condition (A). The lines represent the best linear fit through the data.

Protocol timeline
Protocol events were scheduled according to habitual bed and wake times. The example shows a protocol for a participant with a habitual wake time of 07:00. Participants were admitted to the laboratory ∼1 h 50 min after their scheduled wake time. Pill administration is denoted by the arrow and occurred 2 h after admission and 2 h prior to the 4-h sleep opportunity.

Thermoregulatory effects of ramelteon on core body temperature, the DPG, and proximal and distal skin temperature sites. Values expressed as means ± SEM. The open circles represent the ramelteon condition and closed circles represent the placebo condition. The 0 point denotes time that ramelteon or placebo were administered. (A) The melatonin agonist, ramelteon significantly reduced core temperature by attenuating the normal daytime circadian rise as seen in placebo. (B) The DPG was increased after ramelteon ingestion relative to placebo. (C) Proximal skin temperature measured at the subclavian vein (T_sub) (D) Distal skin temperature measured at the dorsal foot (T_ft).