Ramelteon

Ramelteon is the first in a new class of sleep agents that selectively binds to the melatonin receptors in the suprachiasmatic nucleus (SCN) . It is used for insomnia, particularly delayed sleep onset. Ramelteon has not been shown to produce dependence and has shown no potential for abuse. (In Vivo) :Ramelteon (p.o.; 0.1 and 1 mg/kg) accelerates reentrainment of running wheel activity rhythm to the new lightdark cycle.Ramelteon (p.o.; 3, 10, and 30 mg/kg) does not affect learning or memory in rats tested by the water maze task and the delayed match to position task, implying that MT1/MT2 receptor agonists have no abuse potential.Ramelteon (0.0001, 0.001, 0.01, and 0.1 mg/kg; p.o.; 8 hours) significantly decreases wakefulness at doses of 0.001, 0.01, and 0.1 mg/kg, increases slow-wave sleep at doses of 0.001, 0.01, and 0.1 mg/kg, and increases rapid eye movement sleep at a dose of 0.1 mg/kg.