A sodium leak current regulates pacemaker activity of adult central pattern generator neurons in Lymnaea stagnalis

PLoS One. 2011 Apr 19;6(4):e18745. doi: 10.1371/journal.pone.0018745.


The resting membrane potential of the pacemaker neurons is one of the essential mechanisms underlying rhythm generation. In this study, we described the biophysical properties of an uncharacterized channel (U-type channel) and investigated the role of the channel in the rhythmic activity of a respiratory pacemaker neuron and the respiratory behaviour in adult freshwater snail Lymnaea stagnalis. Our results show that the channel conducts an inward leak current carried by Na(+) (I(Leak-Na)). The I(Leak-Na) contributed to the resting membrane potential and was required for maintaining rhythmic action potential bursting activity of the identified pacemaker RPeD1 neurons. Partial knockdown of the U-type channel suppressed the aerial respiratory behaviour of the adult snail in vivo. These findings identified the Na(+) leak conductance via the U-type channel, likely a NALCN-like channel, as one of the fundamental mechanisms regulating rhythm activity of pacemaker neurons and respiratory behaviour in adult animals.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aging / drug effects
  • Aging / physiology*
  • Amino Acid Sequence
  • Animals
  • Behavior, Animal / drug effects
  • Biological Clocks / drug effects
  • Biological Clocks / physiology*
  • Calcium / pharmacology
  • Cell Membrane / drug effects
  • Cell Membrane / metabolism
  • Cell Separation
  • Electricity
  • Extracellular Space / drug effects
  • Extracellular Space / metabolism
  • Gadolinium / pharmacology
  • Gene Knockdown Techniques
  • Ion Channel Gating / drug effects
  • Ion Channel Gating / physiology*
  • Lymnaea / drug effects
  • Lymnaea / physiology*
  • Membrane Potentials / drug effects
  • Molecular Sequence Data
  • Neurons / drug effects
  • Neurons / physiology*
  • RNA, Double-Stranded / metabolism
  • Sequence Alignment
  • Sodium Channels / chemistry
  • Sodium Channels / metabolism*


  • RNA, Double-Stranded
  • Sodium Channels
  • Gadolinium
  • Calcium