Effects of hypoxia on pulmonary microvascular volume. Am J Physiol Heart Circ Physiol 2000 Sep;279(3):H1274-82
Date
09/20/2000Pubmed ID
10993794DOI
10.1152/ajpheart.2000.279.3.H1274Scopus ID
2-s2.0-0033826620 (requires institutional sign-in at Scopus site) 16 CitationsAbstract
To determine the effects of alveolar hypoxia on pulmonary microvascular volume, X-ray microfocal angiographic images of isolated perfused dog lung lobes were obtained during passage of a bolus of radiopaque contrast medium during both normoxic (alveolar gas, 15% O(2), 6% CO(2), and 79% N(2)) and hypoxic (3% O(2), 6% CO(2), and 91% N(2)) conditions. Regions of interest (ROIs) over the lobar artery and vein at low magnification and a feeding artery ( approximately 500 microm diameter) and the nearby microvasculature (vessels smaller than approximately 50 microm) at high magnification were identified, and X-ray absorbance vs. time curves were acquired under both conditions from the same ROIs. The total pulmonary vascular volume was calculated from the flow and the mean transit time for the contrast medium passage from the lobar artery to lobar vein. The fractional changes in microvascular volume were determined from the areas under the high-magnification X-ray absorbance curves. Hypoxia decreased lobar volume by 13 +/- 3% (SE) and regional microvascular volume by 26 +/- 4% (SE). Given the morphometry of the lung vasculature, these results suggest that capillary volume was decreased by hypoxia.
Author List
Clough AV, Haworth ST, Ma W, Dawson CAAuthor
Anne Clough PhD Professor in the Mathematics, Statistics, and Computer Science department at Marquette UniversityMESH terms used to index this publication - Major topics in bold
AnimalsBlood Flow Velocity
Blood Pressure
Blood Volume
Contrast Media
Dogs
Hypoxia
In Vitro Techniques
Lung
Microcirculation
Perfusion
Pulmonary Circulation
Radiography
Serotonin
Vasoconstriction
