Document Detail

Chronic intermittent hypoxia in humans during 28 nights results in blood pressure elevation and increased muscle sympathetic nerve activity.
MedLine Citation:
PMID:  20581089     Owner:  NLM     Status:  MEDLINE    
Chronic intermittent hypoxia (CIH) is thought to be responsible for the cardiovascular disease associated with obstructive sleep apnea (OSA). Increased sympathetic activation, altered vascular function, and inflammation are all putative mechanisms. We recently reported (Tamisier R, Gilmartin GS, Launois SH, Pepin JL, Nespoulet H, Thomas RJ, Levy P, Weiss JW. J Appl Physiol 107: 17-24, 2009) a new model of CIH in healthy humans that is associated with both increases in blood pressure and augmented peripheral chemosensitivity. We tested the hypothesis that exposure to CIH would also result in augmented muscle sympathetic nerve activity (MSNA) and altered vascular reactivity contributing to blood pressure elevation. We therefore exposed healthy subjects between the ages of 20 and 34 yr (n = 7) to 9 h of nocturnal intermittent hypoxia for 28 consecutive nights. Cardiovascular and hemodynamic variables were recorded at three time points; MSNA was collected before and after exposure. Diastolic blood pressure (71 +/- 1.3 vs. 74 +/- 1.7 mmHg, P < 0.01), MSNA [9.94 +/- 2.0 to 14.63 +/- 1.5 bursts/min (P < 0.05); 16.89 +/- 3.2 to 26.97 +/- 3.3 bursts/100 heartbeats (hb) (P = 0.01)], and forearm vascular resistance (FVR) (35.3 +/- 5.8 vs. 55.3 +/- 6.5 mmHg x ml(-1) x min x 100 g tissue, P = 0.01) all increased significantly after 4 wk of exposure. Forearm blood flow response following ischemia of 15 min (reactive hyperemia) fell below baseline values after 4 wk, following an initial increase after 2 wk of exposure. From these results we conclude that the increased blood pressure following prolonged exposure to CIH in healthy humans is associated with sympathetic activation and augmented FVR.
G S Gilmartin; M Lynch; R Tamisier; J W Weiss
Related Documents :
1901459 - Increase in sympathetic activity with age. i. role of impairment of arterial baroreflexes.
12499579 - Effects of fragrance inhalation on sympathetic activity in normal adults.
23134909 - Status of blood pressure among individuals consuming saline water.
23154589 - Aliskiren vs. other antihypertensive drugs in the treatment of hypertension: a meta-ana...
22316169 - Lung recruitment in ards: we are still confused, but on a higher peep level.
25103629 - Family physicians' quality interventions and performance improvement for hypertension t...
2051389 - Measuring pressures under maxillary complete dentures during swallowing at various occl...
22923629 - Prevalence, awareness, treatment and control of hypertension in a self-selected sub-sah...
16523329 - Respiratory load compensation during mechanical ventilation--proportional assist ventil...
Publication Detail:
Type:  Journal Article     Date:  2010-06-25
Journal Detail:
Title:  American journal of physiology. Heart and circulatory physiology     Volume:  299     ISSN:  1522-1539     ISO Abbreviation:  Am. J. Physiol. Heart Circ. Physiol.     Publication Date:  2010 Sep 
Date Detail:
Created Date:  2010-08-31     Completed Date:  2010-09-22     Revised Date:  2014-08-26    
Medline Journal Info:
Nlm Unique ID:  100901228     Medline TA:  Am J Physiol Heart Circ Physiol     Country:  United States    
Other Details:
Languages:  eng     Pagination:  H925-31     Citation Subset:  IM    
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Anoxia / physiopathology*
Blood Pressure / physiology*
Forearm / blood supply*,  physiopathology
Hyperemia / physiopathology
Ischemia / physiopathology
Muscle, Skeletal / innervation,  physiopathology*
Sympathetic Nervous System / physiopathology*
Grant Support

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

Previous Document:  Molecular mechanisms mediating preconditioning following chronic ischemia differ from those in class...
Next Document:  Electrophysiological studies of transgenic long QT type 1 and type 2 rabbits reveal genotype-specifi...