| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
|
|
|
|||||||
|
|||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
1 Bioengineering, University of California, San Diego, La Jolla, CA, USA; La Jolla Bioengineering Institute, La Jolla, CA, USA
2 Bioengineering, University of California, San Diego, La Jolla, CA, USA
3 La Jolla Bioengineering Institute, La Jolla, CA, USA
4 Departments of Physiology, Bioengineering, and the Institute of Environmental Medicine, University of Pennsylvania, Philadelphia, PA, USA
* To whom correspondence should be addressed. E-mail: agtsai{at}ucsd.edu.
We tested the hypothesis that high viscosity plasma (HV) in extreme hemodilution causes wall shear stress to be greater than low viscosity plasma (LV), leading to enhanced production of NO. Perivascular concentration of nitric oxide (NO) was measured in arterioles and venules and the tissue of the hamster chamber window model, subjected to acute extreme hemodilution, hematocrit (HCT) of 11% using dextran 500 kDa (n=6) or dextran 70 kDa (n=5) with final plasma viscosities of 1.99 ± 0.11 cp and 1.33 ± 0.04 cp respectively. HV significantly increased periarteriolar, perivenular and tissue NO concentration by 2.0, 1.9 and 1.4 times the control (n = 7). NO concentration with LV was not statistically different from control. Arteriolar shear stress was significantly increased in HV relative to LV in arteriolar, but not in venules. Aortic endothelial nitric oxide synthase (eNOS) protein expression was increased with HV, but not with LV. There was a weak correlation between perivascular NO concentration and the locally calculated shear stress induced by the procedures, when blood viscosity was corrected according to HCT values previously determined in studies of microvascular HCT distribution. The finding that periarteriolar and venular NO concentration in HV was the same although arteriolar shear stress was significantly greater than venular shear stress maybe be due to differences in vessel wall metabolism between arterioles and venules and the presence of transport of NO through the blood stream in the microcirculation. Results support the concept that in extreme hemodilution high viscosity plasma maintains functional capillary density (FCD) through a NO-mediated vasodilatation.
This article has been cited by other articles:
|
|
 |
|
  O. Yalcin, P. Ulker, U. Yavuzer, H. J. Meiselman, and O. K. Baskurt Nitric oxide generation by endothelial cells exposed to shear stress in glass tubes perfused with red blood cell suspensions: role of aggregation Am J Physiol Heart Circ Physiol, May 1, 2008; 294(5): H2098 - H2105. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 B. Y. Salazar Vazquez, P. Cabrales, A. G. Tsai, P. C. Johnson, and M. Intaglietta Lowering of Blood Pressure by Increasing Hematocrit with Non Nitric Oxide Scavenging Red Blood Cells Am. J. Respir. Cell Mol. Biol., February 1, 2008; 38(2): 135 - 142. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
P. Cabrales Effects of erythrocyte flexibility on microvascular perfusion and oxygenation during acute anemia Am J Physiol Heart Circ Physiol, August 1, 2007; 293(2): H1206 - H1215. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. T. McLaren, P. A. Marsden, C. D. Mazer, A. J. Baker, D. J. Stewart, A. K. Y. Tsui, X. Li, Y. Yucel, M. Robb, S. R. Boyd, et al. Increased expression of HIF-1{alpha}, nNOS, and VEGF in the cerebral cortex of anemic rats Am J Physiol Regulatory Integrative Comp Physiol, January 1, 2007; 292(1): R403 - R414. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. G. Tsai, P. Cabrales, B. N. Manjula, S. A. Acharya, R. M. Winslow, and M. Intaglietta Dissociation of local nitric oxide concentration and vasoconstriction in the presence of cell-free hemoglobin oxygen carriers Blood, November 15, 2006; 108(10): 3603 - 3610. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
P. Cabrales and A. G. Tsai Plasma viscosity regulates systemic and microvascular perfusion during acute extreme anemic conditions Am J Physiol Heart Circ Physiol, November 1, 2006; 291(5): H2445 - H2452. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
P. Cabrales, J. Martini, M. Intaglietta, and A. G. Tsai Blood viscosity maintains microvascular conditions during normovolemic anemia independent of blood oxygen-carrying capacity Am J Physiol Heart Circ Physiol, August 1, 2006; 291(2): H581 - H590. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 D. B. Kim-Shapiro, A. N. Schechter, and M. T. Gladwin Unraveling the Reactions of Nitric Oxide, Nitrite, and Hemoglobin in Physiology and Therapeutics Arterioscler Thromb Vasc Biol, April 1, 2006; 26(4): 697 - 705. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. Kavdia and A. S. Popel Venular endothelium-derived NO can affect paired arteriole: a computational model Am J Physiol Heart Circ Physiol, February 1, 2006; 290(2): H716 - H723. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
O. Yalcin, F. Aydin, P. Ulker, M. Uyuklu, F. Gungor, J. K. Armstrong, H. J. Meiselman, and O. K. Baskurt Effects of red blood cell aggregation on myocardial hematocrit gradient using two approaches to increase aggregation Am J Physiol Heart Circ Physiol, February 1, 2006; 290(2): H765 - H771. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
P. Cabrales, A. G. Tsai, R. M. Winslow, and M. Intaglietta Extreme hemodilution with PEG-hemoglobin vs. PEG-albumin Am J Physiol Heart Circ Physiol, December 1, 2005; 289(6): H2392 - H2400. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
| Visit Other APS Journals Online |
