Inhibition by Somatostatin Interneurons in Olfactory Cortex
Adam M Large1, Nicholas A Kunz1, Samantha L Mielo1
1Department of Neuroscience and Center for the Neural Basis of Cognition, University of Pittsburgh Pittsburgh, PA, USA.
Frontiers in Neural Circuits
|September 2, 2016
Summary
Somatostatin (SST) interneurons in the piriform cortex broadly inhibit other neurons, including pyramidal cells and other interneurons. This suggests SST cells regulate olfactory processing by controlling excitation and the overall inhibitory network.
Area of Science:
- Neuroscience
- Olfactory Processing
- Cortical Circuitry
Background:
- Inhibitory interneurons are crucial for cortical network function.
- Transgenic mice have advanced understanding of neocortical inhibitory circuits.
- Piriform cortex inhibitory circuitry remains less understood than neocortical circuits.
Purpose of the Study:
- Investigate somatostatin (SST) interneuron inhibition in the piriform cortex.
- Characterize SST and parvalbumin (PV) interneuron distributions and properties.
- Examine SST inhibition of pyramidal cells (PCs) and other interneurons.
Main Methods:
- Utilized transgenic mouse lines (SST-cre, GIN, PV-cre, G42) for cell targeting.
- Recorded anatomical distributions and intrinsic electrophysiological properties.
- Performed in vivo recordings and cell characterization in the piriform cortex.
Main Results:
- SST and PV cell distributions were sparse in piriform cortex compared to neocortex.
- Many recorded SST interneurons exhibited fast-spiking (FS) properties.
- SST cells were found to broadly inhibit unidentified interneurons, PV cells, and other SST cells.
- SST cells inhibit pyramidal cell dendrites, impacting synaptic integration.
Conclusions:
- SST interneurons play a significant role in piriform cortex circuitry.
- SST cells regulate both excitation and the global inhibitory network during olfactory processing.
- Findings highlight the importance of SST interneurons in olfactory sensory processing.
Keywords:
inhibitory connectionsoptogenetic stimulationparvalbumin interneuronspiriform cortexsomatostatin interneuronsMore Related Videos
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