Glycinergic interneurons are functionally integrated into the inspiratory network of mouse medullary slices

Pflugers Arch. 2009 Jul;458(3):459-69. doi: 10.1007/s00424-009-0647-1. Epub 2009 Feb 24.


Neuronal activity in the respiratory network is functionally dependent on inhibitory synaptic transmission. Using two-photon excitation microscopy, we analyzed the integration of glycinergic neurons in the isolated inspiratory pre-Bötzinger complex-driven network of the rhythmic slice preparation. Inspiratory (96%) and 'tonic' expiratory neurons (4%) were identified via an increase or decrease, respectively, of the cytosolic free calcium concentration during the inspiratory-related respiratory burst. Furthermore, in BAC-transgenic mice expressing EGFP under the control of the GlyT2-promoter, 50% of calcium-imaged inspiratory neurons were glycinergic. Inspiratory bursting of glycinergic neurons in the slice was confirmed by whole-cell recording. We also found glycinergic neurons that receive phasic inhibition from other glycinergic neurons. Our calcium imaging data show that glycinergic neurons comprise a large population of inspiratory neurons in the pre-Bötzinger complex-driven network of the rhythmic slice preparation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Action Potentials / physiology*
  • Animals
  • Biological Clocks / physiology*
  • Brain Stem / physiology*
  • Cells, Cultured
  • Glycine / metabolism*
  • Inhalation / physiology*
  • Interneurons / physiology*
  • Mice
  • Mice, Transgenic
  • Nerve Net / physiology*
  • Neural Inhibition / physiology


  • Glycine