K(+) and Ca²(+) dependence of inspiratory-related rhythm in novel "calibrated" mouse brainstem slices

Respir Physiol Neurobiol. 2011 Jan 31;175(1):37-48. doi: 10.1016/j.resp.2010.09.004. Epub 2010 Sep 15.


Recently developed transversal newborn rat brainstem slices with "calibrated" rostrocaudal margins unraveled novel features of rhythmogenic inspiratory active pre-Bötzinger complex (preBötC) neural networks (Ballanyi and Ruangkittisakul, 2009). For example, slice rhythm in physiological (3 mM) superfusate K(+) is depressed by modestly raised Ca²(+) and restored by raised K(+). Correspondingly, we generated here calibrated preBötC slices from commonly used newborn C57BL/6 mice in which rostrocaudal extents of respiratory marker structures, e.g., the inferior olive, turned out to be smaller than in newborn rats. Slices of 400-600 μm thickness with likely centered preBötC kernel ("m-preBötC slices") generated rhythm in 3 mM K(+) and 1mM Ca(2+) for several hours although its rate decreased to < 5 bursts/min after >1 h. Rhythm was stable at 8-12 bursts/min in 6-7 mM K(+), depressed by 2 mM Ca²(+), and restored by 9 mM K(+). Our findings provide the basis for future structure-function analyses of the mouse preBötC, whose activity depends critically on a "Ca(+)/K(+) antagonism" as in rats.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Action Potentials / physiology
  • Age Factors
  • Analysis of Variance
  • Animals
  • Animals, Newborn
  • Brain Stem / cytology
  • Brain Stem / physiology*
  • Calcium / metabolism*
  • Calibration
  • Dose-Response Relationship, Drug
  • In Vitro Techniques
  • Inhalation / drug effects
  • Inhalation / physiology*
  • Mice
  • Mice, Inbred C57BL
  • Neurons / physiology
  • Periodicity*
  • Phosphodiesterase 4 Inhibitors / pharmacology
  • Potassium / metabolism*
  • Potassium / pharmacology
  • Rats
  • Rolipram / pharmacology


  • Phosphodiesterase 4 Inhibitors
  • Rolipram
  • Potassium
  • Calcium