Document Detail


Circulatory effects of apnoea in elite breath-hold divers.
MedLine Citation:
PMID:  19254286     Owner:  NLM     Status:  In-Process    
Abstract/OtherAbstract:
AIM: Voluntary apnoea induces several physiological adaptations, including bradycardia, arterial hypertension and redistribution of regional blood flows. Elite breath-hold divers (BHDs) are able to maintain very long apnoea, inducing severe hypoxaemia without brain injury or black-out. It has thus been hypothesized that they develop protection mechanisms against hypoxia, as well as a decrease in overall oxygen uptake. METHODS: To test this hypothesis, the apnoea response was studied in BHDs and non-divers (NDs) during static and dynamic apnoeas (SA, DA). Heart rate, arterial oxygen saturation (SaO(2)), and popliteal artery blood flow were recorded to investigate the oxygen-conserving effect of apnoea response, and the internal carotid artery blood flow was used to examine the mechanisms of cerebral protection. RESULTS: The bradycardia and peripheral vasoconstriction were accentuated in BHDs compared with NDs (P < 0.01), in association with a smaller SaO(2) decrease (-2.7% vs. -4.9% during SA, P < 0.01 and -6% vs. -11.3% during DA, P < 0.01). Greater increase in carotid artery blood flow was also measured during apnoea in BHDs than in controls. CONCLUSION: These results confirm that elite divers present a potentiation of the well-known apnoea response in both SA and DA conditions. This response is associated with higher brain perfusion which may partly explain the high levels of world apnoea records.
Authors:
Fabrice Joulia; F Lemaitre; P Fontanari; M L Mille; P Barthelemy
Related Documents :
10711776 - Investigation on cerebral hemodynamics in patients with carotid disease receiving carot...
18824786 - Three-dimensional modelling of the human carotid artery using the lattice boltzmann met...
7218496 - Angiographic changes associated with recurrent reduction of carotid and cerebral blood ...
11009266 - Cerebral hemodynamics in carotid sinus syndrome and atrioventricular block.
20693786 - Facts versus theories: an everlasting struggle. the johann jakob wepfer award 2010.
7976376 - Effects of cyproheptadine on txb2 and 6-keto-pgf1 alpha plasma levels in rabbits with h...
Publication Detail:
Type:  Journal Article     Date:  2009-02-28
Journal Detail:
Title:  Acta physiologica (Oxford, England)     Volume:  197     ISSN:  1748-1716     ISO Abbreviation:  Acta Physiol (Oxf)     Publication Date:  2009 Sep 
Date Detail:
Created Date:  2009-08-18     Completed Date:  -     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  101262545     Medline TA:  Acta Physiol (Oxf)     Country:  England    
Other Details:
Languages:  eng     Pagination:  75-82     Citation Subset:  IM    
Affiliation:
UMR MD2 P2COE, IFR Jean Roche, Faculté de Médecine secteur Nord Marseille, Marseilles, France. joulia@univ-tln.fr
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Ageing influences myonuclear domain size differently in fast and slow skeletal muscle of rats.
Next Document:  Experimental hyperhomocysteinaemia: differences in tissue metabolites between homocystine and methio...