CO2-Induced Depolarization of Neurons in Nucleus Tractus Solitarii: A Potential Substrate for Central Chemoreceptors

  • J. B. Dean
  • D. E. Millhorn
Conference paper


Although hypercapnia typically inhibits neural activity in most regions of the central nervous system [3], certain neurons in the medulla oblongata are stimulated during exposure to CO2 and/or H+. Such neurons may serve as chemoreceptors and mediate increased cardiorespiratory activity during hypercapnia and acidosis. Present dogma states that the central chemoreceptors are located exclusively in discrete areas along the ventrolateral surface of the medulla oblongata (VLM) [2, 16]. Results from several laboratories, however, dispute this claim and suggest that other regions of the brainstem may also contain chemosensitive neurons [1, 4, 6, 7, 14, 15, 17–19]. Thus, the precise locations of chemosensitive neurons have not been established [19].


Medulla Oblongata Nucleus Tractus Solitarius Central Chemoreceptor Increase Firing Rate Nucleus Tractus Solitarius Neuron 
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© Springer-Verlag Berlin Heidelberg 1991

Authors and Affiliations

  • J. B. Dean
  • D. E. Millhorn

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