Glial Modulation of CO2 Chemosensory Excitability in the Retrotrapezoid Nucleus of Rodents

  • Joseph S. Erlichman
  • Robert W. Putnam
  • J. C. Leiter
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 605)

We investigated the possibility that astrocytes modify the extracellular milieu and thereby modify the activity of central CO2 chemosensory neurons. The ability of astrocytes to modify the extracellular milieu is heterogeneously distributed among chemosensory sites that have, at least nominally, the same function. The differences in astrocytic activity may make some central chemosensory sites better attuned to the local brain tissue environment and other chemosensory sites better suited to integrate chemosensory activity from multiple sites within and outside the central nervous system.


Extracellular Milieu Extracellular Potassium Hypercapnic Acidosis Astrocytic Activity Chemosensory Neuron 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Chernov, M.M., Daubenspeck, J.A., Denton, J.S., Pfeiffer, J.R., Putnam, R.W. and Leiter, J.C. (2007) A computational analysis of central CO2 chemosensitivity in Helix aspersa. Am. J. Physiol. 292, C278–291.CrossRefGoogle Scholar
  2. Deitmer, J.W. and Rose, C.R. (1996) pH regulation and proton signaling by glial cells. Prog. Neurobiol. 48, 73–103.CrossRefPubMedGoogle Scholar
  3. Erlichman, J.S., Li, A. and Nattie, E.E. (1998) Ventilatory effects of glial dysfunction in a rat brain stem chemoreceptor region. J. Appl. Physiol. 85, 1599–1604.PubMedGoogle Scholar
  4. Erlichman, J.S., Cook, A., Schwab, M.C., Budd, T.W. and Leiter, J.C. (2004) Heterogeneous patterns of pH regulation in glial cells in the dorsal and ventral medulla. Am. J. Physiol. 286, R289–R302.Google Scholar
  5. Filosa, J.A., Dean, J.B. and Putnam, R.W. (2002) Role of intracellular and extracellular pH in the chemosensitive response of rat locus coeruleus neurones. J. Physiol. (Lond) 541.2, 493–509.CrossRefGoogle Scholar
  6. Fukuda, Y. and Honda, Y. (1976) pH sensitivity of cells located at the ventrolaeral surface of the cat medulla oblongata in vitro. Pflügers Arch. - Eur. J. Physiol. 364, 243–247.CrossRefGoogle Scholar
  7. Fukuda, Y., Honda, Y., Schläfke, M.E. and Loeschke, H.H. (1978) Effect of H+ on the membrane potential of silent cells in the ventral and dorsal surface layers of the rat medulla in vitro. Pflugers Arch. 376, 229–235.CrossRefPubMedGoogle Scholar
  8. Nishimura, M., Johnson, D.C., Hitzig, B.M., Okunieff, P. and Kazemi, H. (1989) Effects of hypercapnia on brain pHi and phosphate metabolite degradation by 31PNMR. J. Appl. Physiol. 66, 2181–2188.CrossRefPubMedGoogle Scholar
  9. Nottingham, S., Leiter, J.C., Wages, P., Buhay, S. and Erlichman, J.S. (2001) Developmental changes in intracellular pH regulation in medullary neurons of the rat. Am. J. Physiol. 281, R1940–R1951.Google Scholar
  10. Putnam, R.W., Filosa, J.A. and Ritucci, N.A. (2004) Cellular mechanisms involved in CO2 and acid sensing in chemosensitive neurons. Am. J. Physiol. 287, C1493–C1526.CrossRefGoogle Scholar
  11. Putnam, R.W., Conrad, S.C., Gdovin, M.J., Erlichman, J.S. and Leiter, J.C. (2005) Neonatal maturation of the hypercapnic ventilatory response and central neural CO2 chemosensitivity. Respir. Physiol. Neurobiol. 149, 165–179.CrossRefPubMedGoogle Scholar
  12. Ritucci, N.A., Erlichman, J.S., Leiter, J.C. and Putnam, R.W. (2005) Response of membrane potential (Vm) and intracellular pH (pHi) to hypercapnia in neurons and astrocytes from rat retrotrapezoid nucleus (RTN). Am. J. Physiol. 289, R851–R861.CrossRefGoogle Scholar
  13. Wang, W., Bradley, S.R. and Richerson, G.B. (2002) Quantification of the response of rat medullary raphe neurones to independent changes in pHo and PCO2. J. Physiol. (Lond) 540.3, 951–970.CrossRefGoogle Scholar

Copyright information

© Springer 2008

Authors and Affiliations

  • Joseph S. Erlichman
  • Robert W. Putnam
  • J. C. Leiter

There are no affiliations available

Personalised recommendations