Inhibitory gradient along the dorsoventral axis in the medial entorhinal cortex.
Local inhibitory microcircuits in the medial entorhinal cortex (MEC) and their role in network activity are little investigated. Using a combination of electrophysiological, optical, and morphological circuit analysis tools, we find that layer II stellate cells are embedded in a dense local inhibitory microcircuit. Specifically, we report a gradient of inhibitory inputs along the dorsoventral axis of the MEC, with the majority of this local inhibition arising from parvalbumin positive (PV+) interneurons. Finally, the gradient of PV+ fibers is accompanied by a gradient in the power of extracellular network oscillations in the gamma range, measured both in vitro and in vivo. The reported differences in the inhibitory microcircuitry in layer II of the MEC may therefore have a profound functional impact on the computational working principles at different locations of the entorhinal network and influence the input pathways to the hippocampus.
Neurowissenschaftliches Forschungszentrum, Charité-Universitätsmedizin, 10117 Berlin, Germany.
Prateep
P
Beed
Anja
A
Gundlfinger
Sophie
S
Schneiderbauer
Jie
J
Song
Claudia
C
Böhm
Andrea
A
Burgalossi
Michael
M
Brecht
Imre
I
Vida
Dietmar
D
Schmitz
D000200:Action Potentials / Q000187:drug effects / Q000502:physiology; D000818:Animals; D000831:Animals, Newborn; D004558:Electric Stimulation; D018728:Entorhinal Cortex / Q000166:cytology*; D005071:Evoked Potentials / Q000502:physiology; D018698:Glutamic Acid / Q000494:pharmacology; D066298:In Vitro Techniques; D053444:Inhibitory Postsynaptic Potentials / Q000187:drug effects / Q000502:physiology*; D007395:Interneurons / Q000187:drug effects / Q000502:physiology*; D008239:Lysine / Q000031:analogs & derivatives / Q000378:metabolism; D009415:Nerve Net / Q000187:drug effects / Q000502:physiology*; D009433:Neural Inhibition / Q000187:drug effects / Q000502:physiology*; D010320:Parvalbumins / Q000378:metabolism; D018408:Patch-Clamp Techniques; D010455:Peptides / Q000378:metabolism; D011108:Polymers; D051381:Rats; D017208:Rats, Wistar; D018709:Statistics, Nonparametric; D050495:Vesicular Inhibitory Amino Acid Transport Proteins / Q000378:metabolism
D010320:Parvalbumins; D010455:Peptides; D011108:Polymers; D050495:Vesicular Inhibitory Amino Acid Transport Proteins; C493406:vesicular GABA transporter; C020749:GAT; D018698:Glutamic Acid; C013411:biocytin; D008239:Lysine