article published yes Hua Hu author 4AC0145C-F248-11E8-B48F-1D18A9856A87 Fabian Roth author David H Vandael author 3AE48E0A-F248-11E8-B48F-1D18A9856A870000-0001-7577-1676 Peter M Jonas author 353C1B58-F248-11E8-B48F-1D18A9856A870000-0001-5001-4804 PeJo department Nanophysiology of fast-spiking, parvalbumin-expressing GABAergic interneurons project Biophysics and circuit function of a giant cortical glutamatergic synapse project Mechanisms of transmitter release at GABAergic synapses project Synaptic communication in neuronal microcircuits project Fast-spiking, parvalbumin-expressing GABAergic interneurons (PV+-BCs) express a complex machinery of rapid signaling mechanisms, including specialized voltage-gated ion channels to generate brief action potentials (APs). However, short APs are associated with overlapping Na+ and K+ fluxes and are therefore energetically expensive. How the potentially vicious combination of high AP frequency and inefficient spike generation can be reconciled with limited energy supply is presently unclear. To address this question, we performed direct recordings from the PV+-BC axon, the subcellular structure where active conductances for AP initiation and propagation are located. Surprisingly, the energy required for the AP was, on average, only ∼1.6 times the theoretical minimum. High energy efficiency emerged from the combination of fast inactivation of Na+ channels and delayed activation of Kv3-type K+ channels, which minimized ion flux overlap during APs. Thus, the complementary tuning of axonal Na+ and K+ channel gating optimizes both fast signaling properties and metabolic efficiency. Hu et al. demonstrate that action potentials in parvalbumin-expressing GABAergic interneuron axons are energetically efficient, which is highly unexpected given their brief duration. High energy efficiency emerges from the combination of fast inactivation of voltage-gated Na+ channels and delayed activation of Kv3 channels in the axon. https://research-explorer.ista.ac.at/download/320/5690/2018_Neuron_Hu.pdf application/pdfno Elsevier2018 eng 00042919210001610.1016/j.neuron.2018.02.024 981156 - 165 https://ist.ac.at/en/news/a-certain-type-of-neurons-is-more-energy-efficient-than-previously-assumed/ Hu, Hua, et al. “Complementary Tuning of Na+ and K+ Channel Gating Underlies Fast and Energy-Efficient Action Potentials in GABAergic Interneuron Axons.” <i>Neuron</i>, vol. 98, no. 1, Elsevier, 2018, pp. 156–65, doi:<a href="https://doi.org/10.1016/j.neuron.2018.02.024">10.1016/j.neuron.2018.02.024</a>. Hu H, Roth F, Vandael DH, Jonas PM. 2018. Complementary tuning of Na+ and K+ channel gating underlies fast and energy-efficient action potentials in GABAergic interneuron axons. Neuron. 98(1), 156–165. Hu H, Roth F, Vandael DH, Jonas PM. Complementary tuning of Na+ and K+ channel gating underlies fast and energy-efficient action potentials in GABAergic interneuron axons. <i>Neuron</i>. 2018;98(1):156-165. doi:<a href="https://doi.org/10.1016/j.neuron.2018.02.024">10.1016/j.neuron.2018.02.024</a> Hu, H., Roth, F., Vandael, D. H., &#38; Jonas, P. M. (2018). Complementary tuning of Na+ and K+ channel gating underlies fast and energy-efficient action potentials in GABAergic interneuron axons. <i>Neuron</i>. Elsevier. <a href="https://doi.org/10.1016/j.neuron.2018.02.024">https://doi.org/10.1016/j.neuron.2018.02.024</a> H. Hu, F. Roth, D.H. Vandael, P.M. Jonas, Neuron 98 (2018) 156–165. Hu, Hua, Fabian Roth, David H Vandael, and Peter M Jonas. “Complementary Tuning of Na+ and K+ Channel Gating Underlies Fast and Energy-Efficient Action Potentials in GABAergic Interneuron Axons.” <i>Neuron</i>. Elsevier, 2018. <a href="https://doi.org/10.1016/j.neuron.2018.02.024">https://doi.org/10.1016/j.neuron.2018.02.024</a>. H. Hu, F. Roth, D. H. Vandael, and P. M. Jonas, “Complementary tuning of Na+ and K+ channel gating underlies fast and energy-efficient action potentials in GABAergic interneuron axons,” <i>Neuron</i>, vol. 98, no. 1. Elsevier, pp. 156–165, 2018. 3202018-12-11T11:45:48Z2025-04-15T08:29:04Z