title: Learning increases intrinsic excitability of hippocampal interneurons.
abstract: Learning-related intrinsic excitability changes of pyramidal neurons via modulation of the postburst afterhyperpolarization (AHP) have been repeatedly demonstrated in multiple brain regions (especially the hippocampus), after a variety of learning tasks, and in multiple species. While exciting and important, the changes in pyramidal neurons are only a part of the neural circuitry involved in successful learning. For a more complete picture of the dynamic learning-related changes in the neural network, changes in inhibitory circuitry must also be systematically examined and characterized. Here we show in young adult rats and mice that learning the hippocampus-dependent trace eyeblink conditioning task induces enhanced inhibition onto CA1 pyramidal neurons mediated, in part, by an increase in intrinsic excitability of somatostatin-positive inhibitory neurons (SOMs). Furthermore, both CA1 pyramidal and SOM interneurons shared a common cellular mechanism (reduction in SK channel-mediated AHP) that led to the learning-induced increased intrinsic excitability.
authors.affiliation: Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60611, USA.
authors.forename: Bridget M
authors.initials: BM
authors.lastname: McKay
authors.forename: M Matthew
authors.initials: MM
authors.lastname: Oh
authors.forename: John F
authors.initials: JF
authors.lastname: Disterhoft
mesh_terms: D000200:Action Potentials / Q000502:physiology*; D000704:Analysis of Variance; D000818:Animals; D003215:Conditioning, Eyelid / Q000502:physiology*; D004558:Electric Stimulation; D004576:Electromyography; D019706:Excitatory Postsynaptic Potentials / Q000187:drug effects / Q000502:physiology*; D018756:GABA Antagonists / Q000494:pharmacology; D049452:Green Fluorescent Proteins / Q000235:genetics; D006624:Hippocampus / Q000166:cytology*; D066298:In Vitro Techniques; D053444:Inhibitory Postsynaptic Potentials / Q000187:drug effects; D007395:Interneurons / Q000502:physiology*; D008297:Male; D051379:Mice; D008822:Mice, Transgenic; D009025:Morpholines / Q000494:pharmacology; D011724:Pyridazines / Q000494:pharmacology; D051381:Rats; D026941:Sodium Channel Blockers / Q000494:pharmacology; D013004:Somatostatin / Q000378:metabolism; D013779:Tetrodotoxin / Q000494:pharmacology
chemical_list: C095804:(+)-(S)-5,5-dimethylmorpholinyl-2-acetic acid; D018756:GABA Antagonists; D009025:Morpholines; D011724:Pyridazines; D026941:Sodium Channel Blockers; C485184:enhanced green fluorescent protein; D049452:Green Fluorescent Proteins; D013779:Tetrodotoxin; D013004:Somatostatin; C049853:gabazine
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