Type-I nNOS neurons orchestrate cortical neural activity and vasomotion

Area of Science:

• Neuroscience
• Vascular Biology
• Cellular Biology

Background:

• The brain's coordination of global neural and vascular dynamics remains poorly understood.
• Type-I nNOS neurons, a genetically distinct interneuron population, are sparsely distributed but possess unique characteristics.

Purpose of the Study:

• To investigate the role of type-I nNOS neurons in orchestrating neural and vascular dynamics.
• To determine if these neurons are essential for inter-hemispheric coordination and global brain function.

Main Methods:

• Unilateral ablation of type-I nNOS neurons in the mouse somatosensory cortex using a novel pharmacological strategy.
• Analysis of neural activity (local field potential, gamma-band power envelope) and vascular dynamics (cerebral blood volume, vasomotion).

Main Results:

• Ablation altered neural activity, decreasing delta-band power and sustained vascular responses.
• Reduced coherence between somatosensory cortex hemispheres in gamma-band power and blood volume.
• Abolished post-stimulus undershoot in cerebral blood volume and decreased resting-state oscillations and vasomotion.

Conclusions:

• Type-I nNOS neurons are indispensable for regulating both neural and vascular dynamics across the whole brain.
• These neurons play a critical role in long-range brain signal coordination.
• Disruption of type-I nNOS neurons may contribute to diseases like neurodegeneration and sleep disturbances.