Authors

Elgueta, C., Köhler, J., & Bartos, M.

Affiliations

Institute of Physiology I, Systemic and Cellular Neuroscience, Albert-Ludwigs University Freiburg, D-79104 Freiburg, Germany.

Application Area

Electrophysiology

Electrophysiological Techniques optogenetics

Abstract

Parvalbumin (PV)-expressing perisoma-inhibiting interneurons (PIIs) of the dentate gyrus integrate rapidly correlated synaptic inputs and generate short-duration action potentials that propagate along the axon to their output synapses, supporting fast inhibitory signalling onto their target cells. Here we show that PV-PIIs in rat and mouse dentate gyrus (DG) integrate their intrinsic activity over time and can turn into a persistent firing mode characterized by the ability to generate long-lasting trains of action potentials at ∼50 Hz in the absence of additional inputs. Persistent firing emerges in the axons remote from the axon initial segment and markedly depends on hyperpolarization-activated cyclic nucleotide-gated channel (HCNC) activation. Persistent firing properties are modulated by intracellular Ca(2+) levels and somatic membrane potential. Detailed computational single-cell PIIs models reveal that HCNC-mediated conductances can contribute to persistent firing during conditions of a shift in their voltage activation curve to more depolarized potentials. Paired recordings from PIIs and their target granule cells show that persistent firing supports strong inhibitory output signalling. Thus, persistent firing may emerge during conditions of intense activation of the network, thereby providing silencing to the circuitry and the maintenance of sparse activity in the dentate gyrus.

Extract

… “A yellow light spot (565 nm pE-100; CoolLED) was applied”…

Product Associated Features

pE-100: A range of compact, simple-to-use, single wavelength illumination systems for screening fluorescence.

Diascopic Technique

-

Live Cell Issues

-

Product Type

pE-100

Journal

The Journal of Neuroscience

Year of Publication

2015

Country of Publication

Germany