Ionic Currents and Endogenous Rhythm Generation in the pre-Bötzinger Complex: Modelling and In Vitro Studies

  • Ilya A. Rybak
  • Natalia A. Shevtsova
  • Walter M. St. John
  • Julian F. R. Paton
  • Olivier Pierrefiche
Conference paper
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 551)


The pre-Bötzinger complex (pBC), a small area in the rostroventrolateral medulla, has been suggested to represent a “kernel” of the mammalian respiratory network1, 2, 3, 4, 5. The in vitro preparations from neonatal rodents containing this area can, under certain experimental conditions, generate an intrinsic rhythmic activity4,5. This activity does not require inhibitory neurotransmission6 and, therefore, is likely to be generated by a population of pacemaker neurons in the pBC1, 2, 3, 4, 5. At the same time, the “decrementing” discharge pattern of rhythmic activity in the pBC recorded in vitro differs from the pattern of respiratory discharges observed under normal conditions in vivo (“eupnoea”) and is similar to gasping pattern7, 8. In order to establish possible relationships of the intrinsic rhythmic activity in the pBC to the respiratory rhythmogenesis in vivo, it is important to analyse the conditions in which this activity occurs in vitro and to compare these conditions with the rhythmogenic conditions during eupnoea and gasping in vivo. According to the preliminary modelling studies9, the in vitro rhythmic activity in the pBC may be dependent on a relative expression of the voltage-gated potassium and persistent sodium currents in pBC neurons. Here we present the results of our combined modelling and in vitro studies performed to test this modelling prediction. Our studies focused on the involvement of the potassium and persistent sodium currents in the endogenous rhythmic activity in the pBC in vitro and on the possible relation of this activity to the genesis of the respiratory oscillations in vivo.


Rhythmic Activity Burst Activity Persistent Sodium Current Respiratory Rhythm Generation External Potassium Concentration 
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Copyright information

© Kluwer Academic/Plenum Publishers, New York 2004

Authors and Affiliations

  • Ilya A. Rybak
    • 1
  • Natalia A. Shevtsova
    • 1
  • Walter M. St. John
    • 2
  • Julian F. R. Paton
    • 3
  • Olivier Pierrefiche
    • 4
  1. 1.School of Biomedical Engineering, Science and Health SystemsDrexel UniversityPhiladelphia
  2. 2.Department of PhysiologyDartmouth Medical SchoolLebanon
  3. 3.Department of Physiology, School of Medical SciencesUniversity of BristolBristolUK
  4. 4.GRAP-JE-UFR de PharmacieAmiensFrance

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