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bioRxiv · 10.1101/2022.01.19.476905

Synaptic and intrinsic potentiation in O-LM interneurons is induced by theta patterns of stimulation

Sammari, M.·Inglebert, Y.·Ankri, N.·Russier, M.·Incontro, S.·Debanne, D.
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Abstract

Oriens lacunosum-moleculare (O-LM) interneurons display a non-conventional form of long-term synaptic potentiation (LTP) conferred by calcium-permeable AMPA receptors (CP-AMPAR). So far, this form of LTP has been induced in O-LM cells by physiologically unrealistic protocols. We report here the induction of both synaptic and intrinsic potentiation in O-LM interneurons following stimulation of afferent glutamatergic inputs in the theta ({theta}) frequency range. LTP is induced by synaptic activation of CP-AMPAR whereas long-term potentiation of intrinsic excitability (LTP-IE) results from the mGluR1-dependent down-regulation of Kv7 voltage-dependent potassium channel and hyperpolarization activated and cyclic nucleotide-gated (HCN) channel through the depletion of phosphatidylinositol-4,5-bi-phosphate (PIP2). LTP and LTP-IE are reversible, demonstrating that both synaptic and intrinsic changes are bidirectional in O-LM cells. We conclude that physiological stimuli such as {theta} patterns induce synaptic and intrinsic potentiation in O-LM interneurons.

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Sammari, M., Inglebert, Y., Ankri, N., Russier, M., Incontro, S., Debanne, D.. 2022-01-21. Synaptic and intrinsic potentiation in O-LM interneurons is induced by theta patterns of stimulation. https://doi.org/10.1101/2022.01.19.476905

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