Two Modes of Respiratory Rhythm Generation in the Newborn Rat Brainstem-Spinal Cord Preparation

  • Hiroshi Onimaru
  • Ikuo Homma
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 605)

Two respiration-related rhythm generators, the pre-Bötzinger complex inspiratory and the parafacial pre-inspiratory rhythm generators, have been identified in the medulla of rodents that produce intrinsic periodic bursts. Although both generators can be independently active under specific conditions, they interact as a coupled oscillator system to regulate the respiratory rhythm. Here, we summarize different mechanisms of modulation of the respiratory rhythm in the brainstem-spinal cord preparation of newborn rats and discuss factors determining rhythm generator dominance. We show two different modes of respiratory rhythm generation in the brainstem-spinal cord preparation that depends on the background stimulation level.


Respiratory Rhythm Ventrolateral Medulla Respiratory Neuron Respiratory Network Ventral Respiratory Group 
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© Springer 2008

Authors and Affiliations

  • Hiroshi Onimaru
  • Ikuo Homma

There are no affiliations available

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