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A targeted extracellular approach for recording long-term firing patterns of excitable cells: a practical guide

Abstract

Excitable cells in many endocrine and neuronal systems display rhythms with periodicities on the order of many minutes. To observe firing patterns that represent the output of these rhythms requires a recording technique that can monitor electrophysiological activity for several hours without affecting cell behavior. A targeted extracellular approach (also known as loose-patch) accomplishes this objective. Because low resistance seals (<20 MΩ) do not influence the cell membrane and because the normal intracellular milieu is maintained, this approach is the least invasive method for monitoring the endogenous electrical activity of single cells. In this report, we detail our use of this technique to record the firing patterns of gonadotropin-releasing hormone (GnRH) neurons in brain slices continuously for several hours.

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Correspondence to Suzanne M. Moenter.

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Published: February 17, 2003

This publication makes use, with permission, of data and methodologies published in Nunemaker CS, DeFazio RA, Moenter SM. Estradiol-sensitive afferents modulate long-term episodic firing patterns of GnRH neurons.Endocrinology 2002; 143:2284–2292, Copyright 2002 by The Endocrine Society.

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Nunemaker, C.S., DeFazio, R.A. & Moenter, S.M. A targeted extracellular approach for recording long-term firing patterns of excitable cells: a practical guide. Biol. Proced. Online 5, 53 (2003). https://doi.org/10.1251/bpo46

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Indexing terms

  • GnRH
  • rhythm
  • single-unit
  • neural network
  • loose-patch
  • extracellular