In:
Proceedings of the National Academy of Sciences, Proceedings of the National Academy of Sciences, Vol. 101, No. 27 ( 2004-07-06), p. 10060-10065
Kurzfassung:
We show that many salient hemodynamic flow properties, which have been difficult or impossible to assess in microvessels in vivo , can be estimated by using microviscometry and fluorescent microparticle image velocimetry in microvessels 〉 20 μm in diameter. Radial distributions in blood viscosity, shear stress, and shear rate are obtained and used to predict axial pressure gradient, apparent viscosity, and endothelial-cell surface-layer thickness in vivo . Based solely on microparticle image velocimetry data, which are readily obtainable during the course of most intravital microscopy protocols from systemically injected particle tracers, we show that the microviscometric method consistently predicted a reduction in local and apparent blood viscosity after isovolemic hemodilution. Among its clinical applications, hemodilution is a procedure that is used to treat various pathologies that require reduction in peripheral vascular-flow resistance. Our results are directly relevant in this context because they suggest that the fractional decrease in systemic hematocrit is ≈25–35% greater than the accompanying fractional decrease in microvascular-flow resistance in vivo . In terms of its fundamental usefulness, the microviscometric method provides a comprehensive quantitative analysis of microvascular hemodynamics that has applications in broad areas of medicine and physiology and is particularly relevant to quantitative studies of angiogenesis, tumor growth, leukocyte adhesion, vascular-flow resistance, tissue perfusion, and endothelial-cell mechanotransduction.
Materialart:
Online-Ressource
ISSN:
0027-8424
,
1091-6490
DOI:
10.1073/pnas.0402937101
Sprache:
Englisch
Verlag:
Proceedings of the National Academy of Sciences
Publikationsdatum:
2004
ZDB Id:
209104-5
ZDB Id:
1461794-8
SSG:
11
SSG:
12
