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Chemoreception pp 535-539 | Cite as

pH Sensitivity of Spinal Cord Rhythm in Fetal Mice in Vitro

  • Jaime Eugenín
  • Estibaliz Ampuero
  • Claudia D. Infante
  • Evelyn Silva
  • Isabel Llona
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 536)

Abstract

The spinal respiratory rhythm generator is a neural network localized at the segments C4-C6 able to produce synchronous long lasting rhythmic bursts of action potentials on both phrenic nerves (Dubayle and Viala, 1996). As other spinal cord rhythms, the spinal respiratory rhythm can be induced in curarized rabbits after cervical transection by administration of nialamide-DOPA (Viala and Freton, 1983). This spinal rhythm can also be induced in the in vitro brainstem-spinal cord preparation from newborn rat or mouse by deep diethyl ether anaesthesia, or bath administration of glutamic acid, N-methyl-D-aspartic acid, amphetamine, 5-hydroxytryptophan, or high potassium concentration (Dubayle and Viala, 1998). It has been shown that the spinal respiratory rhythm recorded from neonatal rat brainstem-spinal cord preparation is sensitive to H+ and CO2 (Dubayle and Viala, 1998). However, in most of the experiments the extent to what this chemosensitive response depends directly on the spinal respiratory generator was undefined, because chemical stimulation or the pharmacological inductors affect also the activity of the medullary respiratory pattern generator and both, the medullary and spinal respiratory oscillators, are coupled (Dubayle and Viala, 1996). Uncoupling of these generators by spinal transection at C2 segment caused the disappearance of the spinal respiratory rhythm in most of the neonatal preparations (Dubayle and Viala, 1998).

Keywords

Ventral Root Fetal Mouse Respiratory Rhythm High Potassium Concentration Superfusion Medium 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer Science+Business Media New York 2003

Authors and Affiliations

  • Jaime Eugenín
    • 1
  • Estibaliz Ampuero
    • 1
  • Claudia D. Infante
    • 1
  • Evelyn Silva
    • 1
  • Isabel Llona
    • 1
  1. 1.Laboratory of Neural systems,Department of BiologyUniversidad de Santiago de Chile,Casilla 40, Correo 33Chile

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