|
|
||||||||
1 Deutsches Herzzentrum Berlin, D-13353 Berlin, Germany; 2 Department of Physiology, University of Arizona, Tucson, Arizona 85724; and 3 Department of Physiology, Freie Universität Berlin, D-14195 Berlin, Germany
A theoretical
model was developed to simulate long-term changes of vessel diameters
during structural adaptation of microvascular networks in response to
tissue needs. The diameter of each vascular segment was assumed to
change with time in response to four local stimuli: endothelial wall
shear stress (
w),
intravascular pressure (P), a flow-dependent metabolic stimulus (M),
and a stimulus conducted from distal to proximal segments along
vascular walls (C). Increases in
w, M, or C or decreases in P
were assumed to stimulate diameter increases. Hemodynamic quantities
were estimated using a mathematical model of network flow. Simulations
were continued until equilibrium states were reached in which the
stimuli were in balance. Predictions were compared with data from
intravital microscopy of the rat mesentery, including topological
position, diameter, length, and flow velocity for each segment of
complete networks. Stable equilibrium states, with realistic
distributions of velocities and diameters, were achieved only when all
four stimuli were included. According to the model, responses to
w and P ensure that diameters
are smaller in peripheral than in proximal segments and are larger in
venules than in corresponding arterioles, whereas M prevents collapse
of networks to single pathways and C suppresses generation of large
proximal shunts.
shear stress; pressure; conducted response; mathematical modeling
This article has been cited by other articles:
![]() |
B. Reglin, T. W. Secomb, and A. R. Pries Structural adaptation of microvessel diameters in response to metabolic stimuli: where are the oxygen sensors? Am J Physiol Heart Circ Physiol, December 1, 2009; 297(6): H2206 - H2219. [Abstract] [Full Text] [PDF] |
||||
![]() |
G. Gruionu, J. B. Hoying, L. G. Gruionu, M. H. Laughlin, and T. W. Secomb Structural adaptation increases predicted perfusion capacity after vessel obstruction in arteriolar arcade network of pig skeletal muscle Am J Physiol Heart Circ Physiol, June 1, 2005; 288(6): H2778 - H2784. [Abstract] [Full Text] [PDF] |
||||
![]() |
G. Gruionu, J. B. Hoying, A. R. Pries, and T. W. Secomb Structural remodeling of mouse gracilis artery after chronic alteration in blood supply Am J Physiol Heart Circ Physiol, May 1, 2005; 288(5): H2047 - H2054. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. R. Pries and T. W. Secomb Control of blood vessel structure: insights from theoretical models Am J Physiol Heart Circ Physiol, March 1, 2005; 288(3): H1010 - H1015. [Abstract] [Full Text] [PDF] |
||||
![]() |
G. S. Krenz and C. A. Dawson Flow and pressure distributions in vascular networks consisting of distensible vessels Am J Physiol Heart Circ Physiol, June 1, 2003; 284(6): H2192 - H2203. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. R. Pries, B. Reglin, and T. W. Secomb Structural response of microcirculatory networks to changes in demand: information transfer by shear stress Am J Physiol Heart Circ Physiol, June 1, 2003; 284(6): H2204 - H2212. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. Zakrzewicz, T. W. Secomb, and A. R. Pries Angioadaptation: Keeping the Vascular System in Shape Physiology, October 1, 2002; 17(5): 197 - 201. [Abstract] [Full Text] [PDF] |
||||
![]() |
L.-F. Zhang Vascular adaptation to microgravity: what have we learned? J Appl Physiol, December 1, 2001; 91(6): 2415 - 2430. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. R. Pries, B. Reglin, and T. W. Secomb Structural adaptation of microvascular networks: functional roles of adaptive responses Am J Physiol Heart Circ Physiol, September 1, 2001; 281(3): H1015 - H1025. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. L. Karau, G. S. Krenz, and C. A. Dawson Branching exponent heterogeneity and wall shear stress distribution in vascular trees Am J Physiol Heart Circ Physiol, March 1, 2001; 280(3): H1256 - H1263. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. M. Quick, W. L. Young, E. F. Leonard, S. Joshi, E. Gao, and T. Hashimoto Model of structural and functional adaptation of small conductance vessels to arterial hypotension Am J Physiol Heart Circ Physiol, October 1, 2000; 279(4): H1645 - H1653. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |