RRC ID 27725
Author Ueta Y, Otsuka T, Morishima M, Ushimaru M, Kawaguchi Y.
Title Multiple layer 5 pyramidal cell subtypes relay cortical feedback from secondary to primary motor areas in rats.
Journal Cereb. Cortex
Abstract Higher-order motor cortices, such as the secondary motor area (M2) in rodents, select future action patterns and transmit them to the primary motor cortex (M1). To better understand motor processing, we characterized "top-down" and "bottom-up" connectivities between M1 and M2 in the rat cortex. Somata of pyramidal cells (PCs) in M2 projecting to M1 were distributed in lower layer 2/3 (L2/3) and upper layer 5 (L5), whereas PCs projecting from M1 to M2 had somata distributed throughout L2/3 and L5. M2 afferents terminated preferentially in upper layer 1 of M1, which also receives indirect basal ganglia output through afferents from the ventral anterior and ventromedial thalamic nuclei. On the other hand, M1 afferents terminated preferentially in L2/3 of M2, a zone receiving indirect cerebellar output through thalamic afferents from the ventrolateral nucleus. While L5 corticopontine (CPn) cells with collaterals to the spinal cord did not participate in corticocortical projections, CPn cells with collaterals to the thalamus contributed preferentially to connections from M2 to M1. L5 callosal projection (commissural) cells participated in connectivity between M1 and M2 bidirectionally. We conclude that the connectivity between M1 and M2 is directionally specialized, involving specific PC subtypes that selectively target lamina receiving distinct thalamocortical inputs.
Volume 24(9)
Pages 2362-76
Published 2014-9
DOI 10.1093/cercor/bht088
PII bht088
PMID 23551921
MeSH Action Potentials / physiology Animals Electric Stimulation Feedback, Physiological / physiology* Immunohistochemistry Microelectrodes Motor Cortex / anatomy & histology Motor Cortex / physiology* Neural Pathways / anatomy & histology Neural Pathways / physiology Neuroanatomical Tract-Tracing Techniques Pyramidal Cells / anatomy & histology Pyramidal Cells / physiology* Rats, Wistar Thalamic Nuclei / anatomy & histology Thalamic Nuclei / physiology
IF 5.437
Times Cited 14
Rats W-Tg(Slc32a1-YFP*)1Yyan(strainID=905) W-Tg(Slc32a1-YFP*)2Yyan(strainID=908)