| Donnelly C, Schmitt S, Cecatto C, Cardoso LHD, Komlódi T, Place N, Kayser B, Gnaiger E (2022) The ABC of hypoxia – what is the norm. Bioenerg Commun 2022.12.v2. https://doi.org/10.26124/bec:2022-0012.v2 |
» Bioenerg Commun 2022.12.v2. 
published online 2022-11-14 v1, 2022-12-22 v2 
Donnelly Chris, Schmitt Sabine, Cecatto Cristiane, Cardoso Luiza HD, Komlodi Timea, Place Nicolas, Kayser Bengt, Gnaiger Erich (BEC 2022.12.v2) Bioenerg Commun
Abstract: 
https://doi.org/10.26124/bec:2022-0012.v2
Hypoxia is a condition of oxygen levels below normoxia and opposite to hyperoxia. We here define the normoxic reference state by three complementary precepts: (A) ambient normoxia at sea level in the contemporary atmosphere and corresponding dissolved O2 concentrations at air saturation of aqueous environments; (B) biological compartmental O2 levels at ambient normoxia under physiological activity of healthy organisms in the absence of environmental stress (e.g. stress in a diving human, a stranded whale, a thermally stressed fish); and (C) O2 levels above the respiratory oxygen control region. In the oxygen control region, the capacity for O2 consumption is compromised by hypoxic partial O2 pressure as evaluated by O2 kinetics of respiration or other critical functions. The ABC of hypoxia distinguishes deviations from these reference points caused by different mechanisms: (∆A) ambient alterations of oxygen levels; (∆B) biological O2 demand exceeding O2 supply under pathological or experimental limitations of convective O2 transport or O2 diffusion; and (∆C) critical oxygen pressure in oxygen kinetics shifted by pathological and toxicological effects or environmental stress. The ABC of hypoxia may be of help in the design and interpretation of in vitro and in vivo experimental studies.
• Keywords: ambient, anoxia, critical O2 pressure pc, functional hypoxia, hyperoxia, hypoxia, limiting O2 pressure pl, normoxia, oxygen O2, O2 concentration cO2 [µM], O2 pressure pO2 [kPa]
• Bioblast editor: Tindle-Solomon L
• O2k-Network Lab: AT Innsbruck Oroboros, CH Lausanne Place N
ORCID: 
Donnelly Chris, Schmitt Sabine, Cecatto Cristiane, Cardoso Luiza HD, Komlodi Timea, Place Nicolas, Kayser Bengt, Gnaiger Erich
From version 1 to v2
- The concept of updated versions of publications in BEC is promoted, to quickly add corrections and minor updates without return to peer review. Another round of peer review is mandatory for a new edition of Living Communications.
- Language does not have the rigorous structure of mathematics to avoid ambiguities. We have two interesting examples in our ABC abstract (v1):
- Reader I:
- (B) biological compartmental O2 levels at ambient normoxia under physiological activity of healthy organisms in the absence of environmental stress (e.g. in a diving human, a stranded whale, a thermally stressed animal); ..
- Reader II:
- (B) biological compartmental O2 levels at ambient normoxia under physiological activity of healthy organisms in the absence of environmental stress (e.g. in a diving human, a stranded whale, a thermally stressed animal); ..
- Reader I:
- (C) control of respiration i.e., O2 levels above the region, where the capacity for O2 consumption is not compromised by partial O2 pressure as evaluated by its kinetics.
- Reader II:
- (C) control of respiration i.e., O2 levels above the region, where the capacity for O2 consumption is not compromised by partial O2 pressure as evaluated by its kinetics.
- Reader I is correct in one case where reader II gets it wrong, but reader I fails to get it right in the other case where reader II gets the intended message. Science relies on 'correct' reading, which should be helped by 'correct' writing. Find out in v2 if you are reader I or reader II, or if you are the 'correct' reader in both cases. Here is the update with emphasized corrections (v2):
- (B) biological compartmental O2 levels at ambient normoxia under physiological activity of healthy organisms in the absence of environmental stress (e.g. stress in a diving human, a stranded whale, a thermally stressed fish);
- (C) O2 levels above the respiratory oxygen control region. In the oxygen control region, the capacity for O2 consumption is compromised by hypoxic partial O2 pressure as evaluated by O2 kinetics of respiration or other critical functions.
Preprint
Labels: MiParea: Respiration, Comparative MiP;environmental MiP, Exercise physiology;nutrition;life style
Stress:Oxidative stress;RONS, Hypoxia
Regulation: Aerobic glycolysis, Flux control, Temperature
Coupling state: ROUTINE
HRR: Oxygraph-2k
Tissue normoxia, BEC
