The role of the central chemoreceptors: a modeling perspective.
After introducing the respiratory control system, a previously developed model of the respiratory chemoreflexes, based on rebreathing test data, is briefly described. This model is used to gain insights into the respiratory chemoreflex characteristics of a selection of individuals, and so discover the role of their central chemoreceptors. The chemoreflex model characteristics for each individual were estimated by adjusting the model parameters so that its predictions fit their rebreathing test results. To gain a steady state description of the control of breathing at rest the chemoreflex model is combined with a model of the cerebrovascular reactivity and converted from P(CO)₂ to [H(+)] chemoreceptor inputs. This description is used to illustrate how acid-base and cerebrovascular reactivity factors affect the environment of the central chemoreceptors and determine their role in breathing control. Finally, a dynamic model incorporating the chemoreflex model, acid-base and cerebrovascular reactivity is used to show the role of the central chemoreceptors in stabilizing breathing during sleep at altitude.
Departments of Physiology & Anaesthesia, University of Toronto, 1 King's College Circle, Toronto, ON, Canada. j.duffin@utoronto.ca
James
J
Duffin
D000818:Animals; D001921:Brain / Q000502:physiology*; D002245:Carbon Dioxide / Q000097:blood; D002628:Chemoreceptor Cells / Q000502:physiology*; D006801:Humans; D008954:Models, Biological; D010100:Oxygen / Q000097:blood; D012143:Respiratory Physiological Phenomena
D002245:Carbon Dioxide; D010100:Oxygen