| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
1 Department of Physiology, Freie Universität Berlin, D-14195 Berlin; 2 Deutsches Herzzentrum Berlin, D-13353 Berlin, Germany; and 3 Department of Physiology, University of Arizona, Tucson, Arizona 85724
Terminal vascular beds continually adapt to changing demands. A theoretical model is used to simulate structural diameter changes in response to hemodynamic and metabolic stimuli in microvascular networks. Increased wall shear stress and decreased intravascular pressure are assumed to stimulate diameter increase. Intravascular partial pressure of oxygen (PO2) is estimated for each segment. Decreasing PO2 is assumed to generate a metabolic stimulus for diameter increase, which acts locally, upstream via conduction along vessel walls, and downstream via metabolite convection. By adjusting the sensitivities to these stimuli, good agreement is achieved between predicted network characteristics and experimental data from microvascular networks in rat mesentery. Reduced pressure sensitivity leads to increased capillary pressure with reduced viscous energy dissipation and little change in tissue oxygenation. Dissipation decreases strongly with decreased metabolic response. Below a threshold level of metabolic response flow shifts to shorter pathways through the network, and oxygen supply efficiency decreases sharply. In summary, the distribution of vessel diameters generated by the simulated adaptive process allows the network to meet the functional demands of tissue while avoiding excessive viscous energy dissipation.
shear stress; pressure; conducted response; oxygen transport; mathematical modeling
This article has been cited by other articles:
|
|
 |
|
  J. C. B. Jacobsen, M. J. Mulvany, and N.-H. Holstein-Rathlou A mechanism for arteriolar remodeling based on maintenance of smooth muscle cell activation Am J Physiol Regulatory Integrative Comp Physiol, April 1, 2008; 294(4): R1379 - R1389. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. Milkiewicz, J. L. Doyle, T. Fudalewski, E. Ispanovic, M. Aghasi, and T. L. Haas HIF-1{alpha} and HIF-2{alpha} play a central role in stretch-induced but not shear-stress-induced angiogenesis in rat skeletal muscle J. Physiol., September 1, 2007; 583(2): 753 - 766. [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]
|
|
|
|
|
|
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]
|
|
|
|
 |
|
 F. le Noble, V. Fleury, A. Pries, P. Corvol, A. Eichmann, and R.S. Reneman Control of arterial branching morphogenesis in embryogenesis: go with the flow Cardiovasc Res, February 15, 2005; 65(3): 619 - 628. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 B. R. Shepherd, H. Y.S. Chen, C. M. Smith, G. Gruionu, S. K. Williams, and J. B. Hoying Rapid Perfusion and Network Remodeling in a Microvascular Construct After Implantation Arterioscler. Thromb. Vasc. Biol., May 1, 2004; 24(5): 898 - 904. [Abstract] [Full Text]
|
|
|
|
|
|
S. M. Peirce, R. J. Price, and T. C. Skalak Spatial and temporal control of angiogenesis and arterialization using focal applications of VEGF164 and Ang-1 Am J Physiol Heart Circ Physiol, March 1, 2004; 286(3): H918 - H925. [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]
|
|
|
|
 |
|
 H. Kurz, P. H. Burri, and V. G. Djonov Angiogenesis and Vascular Remodeling by Intussusception: From Form to Function Physiology, April 1, 2003; 18(2): 65 - 70. [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]
|
|
|
|
 |
|
 A. R. Pries, B. Reglin, and T. W. Secomb Structural Adaptation of Vascular Networks: Role of the Pressure Response Hypertension, December 1, 2001; 38(6): 1476 - 1479. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |
