| First Author | Rock C | Year | 2018 |
| Journal | Cereb Cortex | Volume | 28 |
| Issue | 4 | Pages | 1154-1167 |
| PubMed ID | 28174907 | Mgi Jnum | J:358673 |
| Mgi Id | MGI:6293935 | Doi | 10.1093/cercor/bhx025 |
| Citation | Rock C, et al. (2018) Cortical Circuits of Callosal GABAergic Neurons. Cereb Cortex 28(4):1154-1167 |
| abstractText | Anatomical studies have shown that the majority of callosal axons are glutamatergic. However, a small proportion of callosal axons are also immunoreactive for glutamic acid decarboxylase, an enzyme required for gamma-aminobutyric acid (GABA) synthesis and a specific marker for GABAergic neurons. Here, we test the hypothesis that corticocortical parvalbumin-expressing (CC-Parv) neurons connect the two hemispheres of multiple cortical areas, project through the corpus callosum, and are a functional part of the local cortical circuit. Our investigation of this hypothesis takes advantage of viral tracing and optogenetics to determine the anatomical and electrophysiological properties of CC-Parv neurons of the mouse auditory, visual, and motor cortices. We found a direct inhibitory pathway made up of parvalbumin-expressing (Parv) neurons which connects corresponding cortical areas (CC-Parv neurons --> contralateral cortex). Like other Parv cortical neurons, these neurons provide local inhibition onto nearby pyramidal neurons and receive thalamocortical input. These results demonstrate a previously unknown long-range inhibitory circuit arising from a genetically defined type of GABAergic neuron that is engaged in interhemispheric communication. |
