Convergent Control of NREM Sleep and Anesthesia by Prefrontal Layer 5 Extratelencephalic Neurons

Area of Science:

• Neuroscience
• Sleep Science
• Anesthesiology

Background:

• Cortical mechanisms suppressing consciousness are not well understood.
• Identifying neuronal circuits involved in anesthesia and sleep is crucial.

Purpose of the Study:

• To identify specific neuronal populations in the prefrontal cortex (PFC) active during anesthesia.
• To investigate the role of these neurons in regulating sleep and anesthetic effects.

Main Methods:

• Utilized chemogenetics to manipulate neuronal activity in mice.
• Identified NREM and Anesthesia Promoting (NAP) neurons as PFC Layer 5 extratelencephalic (L5 ET) neurons.
• Examined neuronal projections and activation patterns using a transgenic mouse line.

Main Results:

• Discovered a subset of PFC excitatory neurons (NAP/L5 ET) uniquely active under anesthesia.
• Chemogenetic activation of NAP neurons enhanced anesthetic potency and deepened NREM sleep.
• Inhibition of NAP neurons reduced anesthetic effects.
• PFC L5 ET neurons primarily project to subcortical areas, not other cortical regions.

Conclusions:

• Identified a novel excitatory PFC circuit (NAP/L5 ET neurons) that promotes both natural and drug-induced unconsciousness.
• These findings offer insights into the neural basis of sleep regulation and anesthetic mechanisms.
• Suggests a potential therapeutic target for modulating consciousness.