A novel network of multipolar bursting interneurons generates theta frequency oscillations in neocortex.
GABAergic interneurons can phase the output of principal cells, giving rise to oscillatory activity in different frequency bands. Here we describe a new subtype of GABAergic interneuron, the multipolar bursting (MB) cell in the mouse neocortex. MB cells are parvalbumin positive but differ from fast-spiking multipolar (FS) cells in their morphological, neurochemical, and physiological properties. MB cells are reciprocally connected with layer 2/3 pyramidal cells and are coupled with each other by chemical and electrical synapses. MB cells innervate FS cells but not vice versa. MB to MB cell as well as MB to pyramidal cell synapses exhibit paired-pulse facilitation. Carbachol selectively induced synchronized theta frequency oscillations in MB cells. Synchrony required both gap junction coupling and GABAergic chemical transmission, but not excitatory glutamatergic input. Hence, MB cells form a distinct inhibitory network, which upon cholinergic drive can generate rhythmic and synchronous theta frequency activity, providing temporal coordination of pyramidal cell output.
Blatow
Maria
M
Department of Clinical Neurobiology, University Hospital for Neurology, Im Neuenheimer Feld 364, 69120, Heidelberg, Germany.
Rozov
Andrei
A
Katona
Istvan
I
Hormuzdi
Sheriar G
SG
Meyer
Axel H
AH
Whittington
Miles A
MA
Caputi
Antonio
A
Monyer
Hannah
H
D000200:Action Potentials / Q000187:drug effects / Q000502:physiology; D000818:Animals; D001683:Biological Clocks / Q000187:drug effects / Q000502:physiology*; D002217:Carbachol / Q000494:pharmacology; D018679:Cholinergic Agonists / Q000494:pharmacology; D003712:Dendrites / Q000378:metabolism / Q000648:ultrastructure; D019706:Excitatory Postsynaptic Potentials / Q000187:drug effects / Q000502:physiology; D017629:Gap Junctions / Q000187:drug effects / Q000378:metabolism; D018698:Glutamic Acid / Q000378:metabolism; D007395:Interneurons / Q000187:drug effects / Q000378:metabolism* / Q000648:ultrastructure; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D019579:Neocortex / Q000378:metabolism* / Q000648:ultrastructure; D009415:Nerve Net / Q000378:metabolism* / Q000648:ultrastructure; D009433:Neural Inhibition / Q000187:drug effects / Q000502:physiology; D009434:Neural Pathways / Q000378:metabolism* / Q000648:ultrastructure; D009473:Neuronal Plasticity / Q000187:drug effects / Q000502:physiology; D009924:Organ Culture Techniques; D017966:Pyramidal Cells / Q000187:drug effects / Q000378:metabolism / Q000648:ultrastructure; D013569:Synapses / Q000187:drug effects / Q000378:metabolism / Q000648:ultrastructure; D009435:Synaptic Transmission / Q000187:drug effects / Q000502:physiology; D013826:Theta Rhythm / Q000187:drug effects*; D005680:gamma-Aminobutyric Acid / Q000378:metabolism
D018679:Cholinergic Agonists; D018698:Glutamic Acid; D005680:gamma-Aminobutyric Acid; D002217:Carbachol