Dataset Information

Influence of Inhaled Amiloride on Lung Fluid Clearance in Response to Normobaric Hypoxia in Healthy Individuals.

ABSTRACT: Wheatley, Courtney M., Sarah E. Baker, Bryan J. Taylor, Manda L. Keller-Ross, Steven C. Chase, Alex R. Carlson, Robert J. Wentz, Eric M. Snyder, and Bruce D. Johnson. Influence of inhaled amiloride on lung fluid clearance in response to normobaric hypoxia in healthy individuals. High Alt Med Biol 18:343-354, 2017.

Aim

To investigate the role of epithelial sodium channels (ENaC) on lung fluid clearance in response to normobaric hypoxia, 20 healthy subjects were exposed to 15 hours of hypoxia (fraction of inspired oxygen [FiO₂]?=?12.5%) on two randomized occasions: (1) inhaled amiloride (A) (1.5?mg/5?mL saline); and (2) inhaled saline placebo (P). Changes in lung fluid were assessed through chest computed tomography (CT) for lung tissue volume (TV), and the diffusion capacity of the lungs for carbon monoxide (DLCO) and nitric oxide (DLNO) for pulmonary capillary blood volume (V_C). Extravascular lung water (EVLW) was derived as TV-V_C and changes in the CT attenuation distribution histograms were reviewed.

Results

Normobaric hypoxia caused (1) a reduction in EVLW (change from baseline for A vs. P, -8.5%?±?3.8% vs. -7.9%?±?5.2%, p?C (53.6%?±?28.9% vs. 53.9%?±?52.3%, p??0.05), and (4) CT attenuation distribution became more negative, leftward skewed, and kurtotic (p?ConclusionAcute normobaric hypoxia caused a reduction in lung fluid that was unaffected by ENaC inhibition through inhaled amiloride. Although possible amiloride-sensitive ENaC may not be necessary to maintain lung fluid balance in response to hypoxia, it is more probable that normobaric hypoxia promotes lung fluid clearance rather than accumulation for the majority of healthy individuals. The observed reduction in interstitial lung fluid means alveolar fluid clearance may not have been challenged.

SUBMITTER: Wheatley CM

PROVIDER: S-EPMC5743027 | biostudies-literature | 2017 Dec

REPOSITORIES: biostudies-literature

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Publications

Influence of Inhaled Amiloride on Lung Fluid Clearance in Response to Normobaric Hypoxia in Healthy Individuals.

Wheatley Courtney M CM Baker Sarah E SE Taylor Bryan J BJ Keller-Ross Manda L ML Chase Steven C SC Carlson Alex R AR Wentz Robert J RJ Snyder Eric M EM Johnson Bruce D BD

High altitude medicine & biology 20170906 4

Wheatley, Courtney M., Sarah E. Baker, Bryan J. Taylor, Manda L. Keller-Ross, Steven C. Chase, Alex R. Carlson, Robert J. Wentz, Eric M. Snyder, and Bruce D. Johnson. Influence of inhaled amiloride on lung fluid clearance in response to normobaric hypoxia in healthy individuals. High Alt Med Biol 18:343-354, 2017.<h4>Aim</h4>To investigate the role of epithelial sodium channels (ENaC) on lung fluid clearance in response to normobaric hypoxia, 20 healthy subjects were exposed to 15 hours of hypox ...[more]

PMID: 28876128

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Dataset Information

Influence of Inhaled Amiloride on Lung Fluid Clearance in Response to Normobaric Hypoxia in Healthy Individuals.

Aim

Results

Publications

Influence of Inhaled Amiloride on Lung Fluid Clearance in Response to Normobaric Hypoxia in Healthy Individuals.

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