This program is designed to provide a multifaceted approach to the study of the physiological significance of blood rheology studies. The long range goal of the proposed research is to contribute to the understanding of the relation of the rheological properties of blood to: 1) the flow of blood in vivo; 2) the diagnosis and treatment of clinical disorders associated with potential rheological disorders.
The specific aims of the present program include: 1) systematic studies of red blood cell (RBC) aggregation induced by proteins and various polymers (e.g., poloxamers, PEGs) in solution or attached to the RBC surface in order to more clearly detail the mechanism(s) of RBC aggregation; 2) continued investigation of specific RBC cellular factors which influence RBC aggregation and thus to explore reasons for differences in aggregation such as those associated with cell age or between red cells from healthy donors; 3) cooperative studies with Dr. Paul C. Johnson (University of California, San Diego) in which poloxamer-coated rat RBC will be utilized in his in vivo rat spinotrapezius muscle preparation in order to determine plasma viscosity-RBC aggregation interactions for selected microvascular flow parameters (i.e., velocity profiles, aggregate dimensions, formation of aggregates); 4) hemorheological evaluation of blood, red cells and white cells from patients whose clinical state is characterized by altered rheological properties of blood (e.g., hypertension, sepsis). Successful completion of the major aims of this program should provide: 1) greater insight into the process of RBC aggregation and the role of cellular factors versus suspending media properties in this phenomenon; 2) quantitative information relevant to the effects of elevated RBC aggregation and plasma viscosity on muscle microvascular blood flow; 3) detailed data regarding the macro- and micro-rheological properties of pathologic blood and the extent to which rheological abnormalities are affected by metabolic state, therapy, and clinical status. Of long range significance is the potential contribution which studies of this type may make to clinical medicine: if the terms """"""""hyperviscosity"""""""" or """"""""hyperviscosity syndrome"""""""" are to be utilized with scientific meaning, a clearer understanding of their etiology, rheologic mechanisms and physiological importance is essential.

National Institute of Health (NIH)
National Heart, Lung, and Blood Institute (NHLBI)
Research Project (R01)
Project #
Application #
Study Section
Hypertension and Microcirculation Study Section (HM)
Program Officer
Moore, Robert Blaine
Project Start
Project End
Budget Start
Budget End
Support Year
Fiscal Year
Total Cost
Indirect Cost
University of Southern California
Schools of Medicine
Los Angeles
United States
Zip Code
Alexy, Tamas; Pais, Eszter; Wenby, Rosalinda B et al. (2015) Abnormal blood rheology and chronic low grade inflammation: possible risk factors for accelerated atherosclerosis and coronary artery disease in Lewis negative subjects. Atherosclerosis 239:248-51
Sonmez, Melda; Ince, Huseyin Yavuz; Yalcin, Ozlem et al. (2013) The effect of alcohols on red blood cell mechanical properties and membrane fluidity depends on their molecular size. PLoS One 8:e76579
Meram, Ece; Yilmaz, Bahar D; Bas, Ceren et al. (2013) Shear stress-induced improvement of red blood cell deformability. Biorheology 50:165-76
Baskurt, Oguz K; Meiselman, Herbert J (2013) Red blood cell mechanical stability test. Clin Hemorheol Microcirc 55:55-62
Ulker, Pinar; Gunduz, Filiz; Meiselman, Herbert J et al. (2013) Nitric oxide generated by red blood cells following exposure to shear stress dilates isolated small mesenteric arteries under hypoxic conditions. Clin Hemorheol Microcirc 54:357-69
Rabai, Miklos; Meiselman, Herbert J; Wenby, Rosalinda B et al. (2012) Analysis of light scattering by red blood cells in ektacytometry using global pattern fitting. Biorheology 49:317-28
Ulker, Pinar; Yaras, Nazmi; Yalcin, Ozlem et al. (2011) Shear stress activation of nitric oxide synthase and increased nitric oxide levels in human red blood cells. Nitric Oxide 24:184-91
Alexy, Tamas; Baskurt, Oguz K; Nemeth, Norbert et al. (2011) Effect of lanthanides on red blood cell deformability and response to mechanical stress: role of lanthanide ionic radius. Biorheology 48:173-83
Gündüz, F; Koçer, G; Ulker, S et al. (2011) Exercise training enhances flow-mediated dilation in spontaneously hypertensive rats. Physiol Res 60:589-97
Uyuklu, Mehmet; Canpolat, Murat; Meiselman, Herbert J et al. (2011) Wavelength selection in measuring red blood cell aggregation based on light transmittance. J Biomed Opt 16:117006

Showing the most recent 10 out of 148 publications