Blunted hypoxic pulmonary vasoconstriction in apnoea divers.
| Autor: | Kelly T; Department of Human Physiology, University of Oregon, Eugene, Oregon, USA., Brown C; Centre for Heart, Lung & Vascular Health, School of Health and Exercise Sciences, University of British Columbia, Kelowna, British Columbia, Canada., Bryant-Ekstrand M; Department of Human Physiology, University of Oregon, Eugene, Oregon, USA., Lord R; School of Sport and Health Sciences, Cardiff Metropolitan University, Cardiff, UK., Dawkins T; School of Sport and Health Sciences, Cardiff Metropolitan University, Cardiff, UK., Drane A; School of Sport and Health Sciences, Cardiff Metropolitan University, Cardiff, UK., Futral JE; Department of Human Physiology, University of Oregon, Eugene, Oregon, USA., Barak O; Department of Physiology, University of Novi Sad, Novi Sad, Serbia., Dragun T; Department of Integrative Physiology, University of Split School of Medicine, Split, Croatia., Stembridge M; School of Sport and Health Sciences, Cardiff Metropolitan University, Cardiff, UK., Spajić B; Faculty of Kinesiology, University of Zagreb, Zagreb, Croatia., Drviš I; Faculty of Kinesiology, University of Zagreb, Zagreb, Croatia., Duke JW; Department of Biological Sciences, Northern Arizona University, Flagstaff, Arizona, USA., Ainslie PN; Centre for Heart, Lung & Vascular Health, School of Health and Exercise Sciences, University of British Columbia, Kelowna, British Columbia, Canada., Foster GE; Centre for Heart, Lung & Vascular Health, School of Health and Exercise Sciences, University of British Columbia, Kelowna, British Columbia, Canada., Dujic Z; Department of Integrative Physiology, University of Split School of Medicine, Split, Croatia., Lovering AT; Department of Human Physiology, University of Oregon, Eugene, Oregon, USA. |
|---|---|
| Jazyk: | angličtina |
| Zdroj: | Experimental physiology [Exp Physiol] 2022 Nov; Vol. 107 (11), pp. 1225-1240. Date of Electronic Publication: 2022 Sep 16. |
| DOI: | 10.1113/EP090326 |
| Abstrakt: | New Findings: What is the central question of this study? Does the hyperbaric, hypercapnic, acidotic, hypoxic stress of apnoea diving lead to greater pulmonary vasoreactivity and increased right heart work in apnoea divers? What is the main finding and its importance? Compared with sex- and age-matched control subjects, divers experienced significantly less change in total pulmonary resistance in response to short-duration isocapnic hypoxia. With oral sildenafil (50 mg), there were no differences in total pulmonary resistance between groups, suggesting that divers can maintain normal pulmonary artery tone in hypoxic conditions. Blunted hypoxic pulmonary vasoconstriction might be beneficial during apnoea diving. Abstract: Competitive apnoea divers dive repetitively to depths >50 m. During the final portions of ascent, divers experience significant hypoxaemia. Additionally, hyperbaria during diving increases thoracic blood volume while simultaneously reducing lung volume and increasing pulmonary artery pressure. We hypothesized that divers would have exaggerated hypoxic pulmonary vasoconstriction, leading to increased right heart work owing to their repetitive hypoxaemia and hyperbaria, and that the administration of sildenafil would have a greater effect in reducing pulmonary resistance in divers. We recruited 16 divers (Divers) and 16 age- and sex-matched non-diving control subjects (Controls). Using a double-blinded, placebo-controlled, cross-over design, participants were evaluated for normal cardiac and lung function, then their cardiopulmonary responses to 20-30 min of isocapnic hypoxia (end-tidal partial pressure of O (© 2022 The Authors. Experimental Physiology © 2022 The Physiological Society.) |
| Databáze: | MEDLINE |
| Externí odkaz: |
|
Plný text