Layer 6b Is Driven by Intracortical Long-Range Projection Neurons.
Cell Rep
; 30(10): 3492-3505.e5, 2020 03 10.
Article
em En
| MEDLINE
| ID: mdl-32160552
ABSTRACT
Layer 6b (L6b), the deepest neocortical layer, projects to cortical targets and higher-order thalamus and is the only layer responsive to the wake-promoting neuropeptide orexin/hypocretin. These characteristics suggest that L6b can strongly modulate brain state, but projections to L6b and their influence remain unknown. Here, we examine the inputs to L6b ex vivo in the mouse primary somatosensory cortex with rabies-based retrograde tracing and channelrhodopsin-assisted circuit mapping in brain slices. We find that L6b receives its strongest excitatory input from intracortical long-range projection neurons, including those in the contralateral hemisphere. In contrast, local intracortical input and thalamocortical input were significantly weaker. Moreover, our data suggest that L6b receives far less thalamocortical input than other cortical layers. L6b was most strongly inhibited by PV and SST interneurons. This study shows that L6b integrates long-range intracortical information and is not part of the traditional thalamocortical loop.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Córtex Cerebral
/
Neurônios
Tipo de estudo:
Prognostic_studies
Limite:
Animals
Idioma:
En
Revista:
Cell Rep
Ano de publicação:
2020
Tipo de documento:
Article