Atrial distension, arterial pulsation, and vasopressin release during negative pressure breathing in humans
1 Department of Aviation Medicine, National University Hospital, DK-2200 Copenhagen; 2 Department of Physiology, University of Southern Denmark, DK-5000 Odense; and 3 Division of Endocrinology, Herlev Hospital, University of Copenhagen, DK-2730 Herlev, Denmark During an antiorthostatic posture ch...
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Published in | American journal of physiology. Heart and circulatory physiology Vol. 281; no. 4; pp. H1583 - H1588 |
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Main Authors | , , , , , |
Format | Journal Article |
Language | English |
Published |
United States
01.10.2001
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Subjects | |
Online Access | Get full text |
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Summary: | 1 Department of Aviation Medicine, National University
Hospital, DK-2200 Copenhagen; 2 Department of Physiology,
University of Southern Denmark, DK-5000 Odense; and
3 Division of Endocrinology, Herlev Hospital, University of
Copenhagen, DK-2730 Herlev, Denmark
During an
antiorthostatic posture change, left atrial (LA) diameter and arterial
pulse pressure (PP) increase, and plasma arginine vasopressin (AVP) is
suppressed. By comparing the effects of a 15-min posture change from
seated to supine with those of 15-min seated negative pressure
breathing in eight healthy males, we tested the hypothesis that with
similar increases in LA diameter, suppression of AVP release is
dependent on the degree of increase in PP. LA diameter increased
similarly during the posture change and negative pressure breathing
( 9 to 24 mmHg) from between 30 and 31 ± 1 to 34 ± 1 mm
( P < 0.05). The increase in PP from 38 ± 2 to
44 ± 2 mmHg ( P < 0.05) was sustained during the
posture change but only increased during the initial 5 min of negative pressure breathing from 36 ± 3 to 42 ± 3 mmHg
( P < 0.05). Aortic transmural pressure decreased
during the posture change and increased during negative pressure
breathing. Plasma AVP was suppressed to a lower value during the
posture change (from 1.5 ± 0.3 to 1.2 ± 0.2 pg/ml,
P < 0.05) than during negative pressure breathing (from 1.5 ± 0.3 to 1.4 ± 0.3 pg/ml). Plasma norepinephrine
was decreased similarly during the posture change and negative pressure breathing compared with seated control. In conclusion, the results are
in compliance with the hypothesis that during maneuvers with similar
cardiac distension, suppression of AVP release is dependent on the
increase in PP and, furthermore, probably unaffected by static aortic
baroreceptor stimulation.
antidiuretic hormone; baroreceptors; blood pressure; sympathetic
nervous system |
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Bibliography: | ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23 |
ISSN: | 0363-6135 1522-1539 |
DOI: | 10.1152/ajpheart.2001.281.4.h1583 |