Dynamic changes in cortical neurotrophic factor-positive interneurons during sleep.

Area of Science:

• Neuroscience
• Sleep Science
• Cortical Circuitry

Background:

• Mammalian sleep involves significant changes in cortical neuron activity, shaping electroencephalographic (EEG) rhythms.
• Inhibitory interneurons (INs) modulate these rhythms through direct inhibition and IN-IN interactions, crucial for understanding sleep's impact on cortical circuits.

Purpose of the Study:

• Investigate the activity patterns of neuroprotective factor-positive (NDNF+) inhibitory interneurons (INs) during natural sleep and following sleep deprivation.
• Elucidate the role of NDNF+ INs in cortical EEG activity and sleep regulation.

Main Methods:

• Utilized genetically encoded calcium imaging (GECI) in freely behaving mice.
• Combined GECI with miniature head-mounted cameras and polysomnography for comprehensive data acquisition.

Main Results:

• NDNF+ INs exhibited peak activity during rapid-eye-movement (REM) sleep.
• A significant decrease in NDNF+ IN activity was observed after total sleep deprivation.

Conclusions:

• NDNF+ INs are dynamically regulated during sleep and show altered activity in response to sleep loss.
• These findings suggest NDNF+ INs play a role in cortical EEG generation during REM sleep and in adaptive responses to sleep deprivation.