Hypoxic ventilatory depression may be due to central chemoreceptor cell hyperpolarization.
By re-examining the results of various studies of HVD, of the localization of medullary CO2 chemosensory cells, and of their acid secretion, an hypothesis has been developed suggesting that the neurones which detect increased CO2 or CSF acid respond to decreased transmembrane H+ gradient, i.e. a greater fall in ECF than in ICF pH. Hypoxic lactic acid generated within these cells depresses activity, which can be restored by an appropriate rise of Paco2, disclosing both normal peripheral chemoreceptor hypoxic sensitivity and normal medullary integrative response.
Severinghaus
J W
JW
Department of Anesthesia, University of California San Francisco, USA.
D002245:Carbon Dioxide / Q000097:blood; D016764:Cell Polarity; D002628:Chemoreceptor Cells / Q000502:physiology*; D006801:Humans; D000860:Hypoxia / Q000503:physiopathology*; D008526:Medulla Oblongata / Q000502:physiology; D010100:Oxygen / Q000008:administration & dosage; D012119:Respiration / Q000502:physiology*
D002245:Carbon Dioxide; D010100:Oxygen