Breakthrough research reveals key role of melatonin receptor in REM sleep

A major breakthrough in the understanding of the sleep mechanism opens new promise for the treatment of sleep disorders and related neuropsychiatric conditions: scientists have identified the melatonin receptor MT1 as a crucial regulator of REM (Rapid Eye Movement) sleep.

REM sleep is crucial for dreaming, memory consolidation and emotional regulation. In the brain, the melatonin MT1 receptor affects a species neuron that synthesizes the neurotransmitter and hormone norepinephrine, found in an area known as the Locus Coeruleus, or ‘blue spot’ in Latin. During REM sleep, these neurons become quieter and stop their activity. Serious conditions such as Parkinson’s disease and Lewy body dementia -; who currently have no effective treatments -; are related to disturbances in REM sleep.

“This discovery not only advances our understanding of sleep mechanisms, but also holds significant clinical potential,” said Gabriella Gobbi, lead researcher of a new study published in the journal The Guardian. Journal of Neuroscience. She is a professor of psychiatry at McGill University, a clinical scientist at the Research Institute of the McGill University Health Centre, and Canada Research Chair in Therapeutics for Mental Health.

The science of snoozing

Human sleep unfolds in a precise sequence of non-REM and REM stages, each of which performs different physiological functions. REM sleep plays a crucial role in memory consolidation and emotional regulation. Non-REM sleep supports physical recovery and repair processes. Disruptions in this cycle can impair cognitive function and increase vulnerability to neuropsychiatric diseases.

Until now, the specific receptor that causes REM sleep had eluded scientists. The new study has identified the melatonin MT1 receptor as a key regulator of this sleep phase. Using a new drug that targets MT1 receptors, researchers have successfully improved the duration of REM sleep in laboratory animals while simultaneously reducing neuronal activity.

Currently, there are no medications that specifically target REM sleep. Most hypnotic medications on the market increase total sleep duration, but tend to negatively impact REM sleep.”

Dr. Stefano Comai, co-senior author of the study and professor at the University of Padua and adjunct professor at McGill University

Further research into the neurobiology and pharmacology of REM sleep is crucial for developing targeted treatments that could improve the quality of life of patients affected by these debilitating diseases, the researchers said. As scientists continue to explore the complexities of sleep regulation, hopes for effective interventions in neurological disorders are becoming increasingly promising.