Neuroscience and Behavioral Physiology

, Volume 37, Issue 7, pp 739–746 | Cite as

Effects of leucine-enkephalin on potassium currents in neurons in the rat respiratory center in vitro

  • A. N. Inyushkin


Experiments to identify the neuronal mechanisms underlying the respiratory activity of the opioid peptide leucine-enkephalin were performed on transverse slices of the rat brainstem in voltage-clamped conditions; studies addressed the effects of this peptide (10 nM–1 µM) on the potassium A current and the inward potassium current of neurons in two areas of the respiratory center: the ventrolateral area of the solitary tract nucleus and the pre-Bötzinger complex. The parameters of the A current assessed in all respiratory center neurons studied showed no change in the presence of leucine-enkephalin. At the same time, leucine-enkephalin produced reversible increases in the amplitude of the inward potassium current. These results provide evidence that the inhibitory effect of leucine-enkephalin at the level of respiratory center neurons is at least in part explained by its stimulatory action on the inward potassium current but is not associated with modulation of the potassium A current.

Key words

respiratory center solitary tract nucleus pre-Bötzinger complex leucine-enkephalin potassium A current inward potassium current 


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Copyright information

© Springer Science+Business Media, Inc. 2007

Authors and Affiliations

  • A. N. Inyushkin
    • 1
  1. 1.Samara State UniversitySamaraRussia

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