title: The Pathway for Oxygen: Tutorial Modelling on Oxygen Transport from Air to Mitochondrion: The Pathway for Oxygen.
abstract: The 'Pathway for Oxygen' is captured in a set of models describing quantitative relationships between fluxes and driving forces for the flux of oxygen from the external air source to the mitochondrial sink at cytochrome oxidase. The intervening processes involve convection, membrane permeation, diffusion of free and heme-bound O2 and enzymatic reactions. While this system's basic elements are simple: ventilation, alveolar gas exchange with blood, circulation of the blood, perfusion of an organ, uptake by tissue, and consumption by chemical reaction, integration of these pieces quickly becomes complex. This complexity led us to construct a tutorial on the ideas and principles; these first PathwayO2 models are simple but quantitative and cover: (1) a 'one-alveolus lung' with airway resistance, lung volume compliance, (2) bidirectional transport of solute gasses like O2 and CO2, (3) gas exchange between alveolar air and lung capillary blood, (4) gas solubility in blood, and circulation of blood through the capillary syncytium and back to the lung, and (5) blood-tissue gas exchange in capillaries. These open-source models are at Physiome.org and provide background for the many respiratory models there.
authors.affiliation: Department of Bioengineering, University of Washington, Seattle, WA, USA. Jbb2@uw.edu.
authors.forename: James B
authors.initials: JB
authors.lastname: Bassingthwaighte
authors.affiliation: Department of Bioengineering, University of Washington, Seattle, WA, USA.
authors.forename: Gary M
authors.initials: GM
authors.lastname: Raymond
authors.affiliation: Department of Physiology, Medical College of Wisconsin, Milwaukee, WI, USA.
authors.forename: Ranjan K
authors.initials: RK
authors.lastname: Dash
authors.affiliation: Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI, USA.
authors.forename: Daniel A
authors.initials: DA
authors.lastname: Beard
authors.affiliation: Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, USA.
authors.forename: Margaret
authors.initials: M
authors.lastname: Nolan
mesh_terms: D001692:Biological Transport; D006801:Humans; D008168:Lung / Q000378:metabolism; D008928:Mitochondria / Q000378:metabolism*; D008954:Models, Biological; D010100:Oxygen / Q000378:metabolism*
chemical_list: D010100:Oxygen
keywords: Blood-tissue oxygen exchange; Mechanics of ventilation; Oxidative phosphorylation; Oxygen transport in blood