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Voltage-dependent currents in neurones of the nuclei of the solitary tract of rat brainstem slices

  • J. Champagnat
  • T. Jacquin
  • D. W. Richter
Excitable Tissues and Central Nervous Physiology

Abstract

Neurones within the ventral and ventrolateral nuclei of the solitary tract were analyzed under single-electrode current- and voltage-clamp conditions in rat brainstem slices. We present direct and indirect evidence for the existence of five different sorts of membrane currents:
  1. 1.

    a tetrodotoxin-sensitive sodium current,

     
  2. 2.

    a tetrodotoxin-resistant calcium current,

     
  3. 3.

    a calcium-dependent potassium current,

     
  4. 4.

    a non-inactivating potassium current which is inhibited by muscarine,

     
  5. 5.

    an inactivating potassium current, which is inhibited by 4-aminopyridine.

     

These membrane properties do not produce spontaneous bursting in these neurones. Assuming that neurones with such properties belong to the respiratory network, we discuss how conductances of this type may be involved in mechanisms regulating central respiratory activity.

Key words

Brainstem slices Nuclei of the solitary tract Respiratory control Single-electrode voltage-clamp Calcium current Potassium currents 

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Copyright information

© Springer-Verlag 1986

Authors and Affiliations

  • J. Champagnat
    • 1
  • T. Jacquin
    • 1
  • D. W. Richter
    • 2
  1. 1.Labotaroire de Physiologie NerveuseCNRSGif-sur-YvetteFrance
  2. 2.I. Physiologisches Institut des Universität HeidelbergHeidelbergFederal Republic of Germany

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