Inhibitory interneuron classes express complementary AMPA-receptor patterns in macaque primary visual cortex.
Glutamate receptors mediate excitatory neurotransmission. A very prevalent type of glutamate receptor in the neocortex is the AMPA receptor (AMPAR). AMPARs mediate fast synaptic transmission and their functionality depends on the subunit composition. In primary visual cortex (area V1), the density and subunit composition of AMPARs differ among cortical layers and among cell types. The AMPARs expressed by the different types of inhibitory interneurons, which are crucial for network function, have not yet been characterized systematically. We investigated the distribution of AMPAR subunits in macaque V1 for three distinct subpopulations of inhibitory interneurons: parvalbumin-immunoreactive (PV-IR) interneurons, calbindin-immunoreactive (CB-IR) interneurons, and calretinin-immunoreactive (CR-IR) interneurons. We found that PV-IR cells, which have previously been identified as fast spiking, show high expression of the GluA2 and GluA3 subunits. In contrast, CB-IR and CR-IR cells, which tend to be intermediate spiking, show high expression of the GluA1 and GluA4 subunits. Thus, our data demonstrate that the expression of AMPARs divides inhibitory interneurons in macaque V1 into two categories that are compatible with existing classification methods based on calcium-binding proteins and firing behavior. Moreover, our findings suggest new approaches to target the different inhibitory interneuron classes pharmacologically in vivo.
Department of Vision and Cognition, Netherlands Institute for Neuroscience, 1105 BA Amsterdam, The Netherlands, Section of Functional Neuroanatomy, Department of Anatomy and Neurosciences, Department of Pathology, Vrije Universiteit Medical Center, 1007 MB Amsterdam, The Netherlands, Department of Integrative Neurophysiology, Center for Neurogenomics and Cognitive Research, Vrije Universiteit, 1081 HV Amsterdam, The Netherlands, and Department of Psychiatry, Academisch Medisch Centrum, 1105 AZ Amsterdam, The Netherlands.
Roxana N
RN
Kooijmans
Matthew W
MW
Self
Floris G
FG
Wouterlood
Jeroen A M
JA
Beliën
Pieter R
PR
Roelfsema
D000818:Animals; D064032:Calbindin 2 / Q000378:metabolism; D064026:Calbindins / Q000378:metabolism; D007395:Interneurons / Q000145:classification* / Q000378:metabolism*; D008253:Macaca mulatta; D008297:Male; D009433:Neural Inhibition / Q000502:physiology*; D010320:Parvalbumins / Q000378:metabolism; D021122:Protein Subunits / Q000378:metabolism; D018091:Receptors, AMPA / Q000378:metabolism*; D014793:Visual Cortex / Q000166:cytology*
D064032:Calbindin 2; D064026:Calbindins; D010320:Parvalbumins; D021122:Protein Subunits; D018091:Receptors, AMPA
AMPA; GluA2; V1; interneurons; macaque; quantification