title: Enhanced intrinsic excitability in basket cells maintains excitatory-inhibitory balance in hippocampal circuits.
abstract: The dynamics of inhibitory circuits in the cortex is thought to rely mainly on synaptic modifications. We challenge this view by showing that hippocampal parvalbumin-positive basket cells (PV-BCs) of the CA1 region express long-term (>30 min) potentiation of intrinsic neuronal excitability (LTP-IE(PV-BC)) upon brief repetitive stimulation of the Schaffer collaterals. LTP-IE(PV-BC) is induced by synaptic activation of metabotropic glutamate receptor subtype 5 (mGluR5) and mediated by the downregulation of Kv1 channel activity. LTP-IE(PV-BC) promotes spiking activity at the gamma frequency (∼35 Hz) and facilitates recruitment of PV-BCs to balance synaptic and intrinsic excitation in pyramidal neurons. In conclusion, activity-dependent modulation of intrinsic neuronal excitability in PV-BCs maintains excitatory-inhibitory balance and thus plays a major role in the dynamics of hippocampal circuits.
authors: INSERM, UMR_S 1072, F-13344 Marseille, France; Aix-Marseille Université, UNIS, F-13344 Marseille, France.
authors: Emilie
authors: E
authors: Campanac
authors: Célia
authors: C
authors: Gasselin
authors: Agnès
authors: A
authors: Baude
authors: Sylvain
authors: S
authors: Rama
authors: Norbert
authors: N
authors: Ankri
authors: Dominique
authors: D
authors: Debanne
mesh_terms: D000200:Action Potentials / Q000502:physiology; D000818:Animals; D000831:Animals, Newborn; D019706:Excitatory Postsynaptic Potentials / Q000502:physiology*; D006624:Hippocampus / Q000166:cytology / Q000502:physiology*; D017774:Long-Term Potentiation / Q000502:physiology*; D009415:Nerve Net / Q000502:physiology*; D009474:Neurons / Q000502:physiology*; D010320:Parvalbumins / Q000378:metabolism; D017966:Pyramidal Cells / Q000502:physiology; D051381:Rats; D017208:Rats, Wistar; D064529:Receptor, Metabotropic Glutamate 5; D018094:Receptors, Metabotropic Glutamate / Q000502:physiology
chemical_list: C578937:Grm5 protein, rat; D010320:Parvalbumins; D064529:Receptor, Metabotropic Glutamate 5; D018094:Receptors, Metabotropic Glutamate