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Strength and duration of perisomatic GABAergic inhibition depend on distance between synaptically connected cells.

ABSTRACT: GABAergic perisoma-inhibiting fast-spiking interneurons (PIIs) effectively control the activity of large neuron populations by their wide axonal arborizations. It is generally assumed that the output of one PII to its target cells is strong and rapid. Here, we show that, unexpectedly, both strength and time course of PII-mediated perisomatic inhibition change with distance between synaptically connected partners in the rodent hippocampus. Synaptic signals become weaker due to lower contact numbers and decay more slowly with distance, very likely resulting from changes in GABAA receptor subunit composition. When distance-dependent synaptic inhibition is introduced to a rhythmically active neuronal network model, randomly driven principal cell assemblies are strongly synchronized by the PIIs, leading to higher precision in principal cell spike times than in a network with uniform synaptic inhibition.

SUBMITTER: Struber M

PROVIDER: S-EPMC4313861 | biostudies-other | 2015 Jan

REPOSITORIES: biostudies-other

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Strength and duration of perisomatic GABAergic inhibition depend on distance between synaptically connected cells.

Strüber Michael M Jonas Peter P Bartos Marlene M

Proceedings of the National Academy of Sciences of the United States of America 20150112 4

GABAergic perisoma-inhibiting fast-spiking interneurons (PIIs) effectively control the activity of large neuron populations by their wide axonal arborizations. It is generally assumed that the output of one PII to its target cells is strong and rapid. Here, we show that, unexpectedly, both strength and time course of PII-mediated perisomatic inhibition change with distance between synaptically connected partners in the rodent hippocampus. Synaptic signals become weaker due to lower contact numbe ...[more]

PMID: 25583495

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Strength and duration of perisomatic GABAergic inhibition depend on distance between synaptically connected cells.

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Strength and duration of perisomatic GABAergic inhibition depend on distance between synaptically connected cells.

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