Format

Send to

Choose Destination
Neuron. 2014 Jan 8;81(1):140-52. doi: 10.1016/j.neuron.2013.09.046. Epub 2013 Dec 12.

Theta-gamma-modulated synaptic currents in hippocampal granule cells in vivo define a mechanism for network oscillations.

Author information

1
IST Austria (Institute of Science and Technology Austria), Am Campus 1, A-3400 Klosterneuburg, Austria. Electronic address: alejandro.pernia-andrade@ist.ac.at.
2
IST Austria (Institute of Science and Technology Austria), Am Campus 1, A-3400 Klosterneuburg, Austria. Electronic address: peter.jonas@ist.ac.at.

Abstract

Theta-gamma network oscillations are thought to represent key reference signals for information processing in neuronal ensembles, but the underlying synaptic mechanisms remain unclear. To address this question, we performed whole-cell (WC) patch-clamp recordings from mature hippocampal granule cells (GCs) in vivo in the dentate gyrus of anesthetized and awake rats. GCs in vivo fired action potentials at low frequency, consistent with sparse coding in the dentate gyrus. GCs were exposed to barrages of fast AMPAR-mediated excitatory postsynaptic currents (EPSCs), primarily relayed from the entorhinal cortex, and inhibitory postsynaptic currents (IPSCs), presumably generated by local interneurons. EPSCs exhibited coherence with the field potential predominantly in the theta frequency band, whereas IPSCs showed coherence primarily in the gamma range. Action potentials in GCs were phase locked to network oscillations. Thus, theta-gamma-modulated synaptic currents may provide a framework for sparse temporal coding of information in the dentate gyrus.

PMID:
24333053
PMCID:
PMC3909463
DOI:
10.1016/j.neuron.2013.09.046
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Elsevier Science Icon for PubMed Central
Loading ...
Support Center