Affiliations: Department of Physiology and Biophysics, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
Note: [] Present address: Department of Internal Medicine, Inje University Sanggye Paik Hospital, Seoul, Korea.
Note: [] Address for correspondence: Dr. Herbert J. Meiselman, Department of Physiology and Biophysics, Keck School of Medicine, 1333 San Pablo St., MMR 626, Los Angeles, CA 90033, USA. Fax: +1 323 442 2283; E-mail: meiselma@usc.edu.
Abstract: Although the study of red blood cell (RBC) aggregation continues to be of basic science and clinical interest, aggregation standards for calibration do not exist, and most aggregation studies report data in terms of arbitrary units: quantitative comparisons between studies are thus essentially precluded. However, use of low shear viscometry plus the Casson equation provides a yield shear stress that has defined units and is known to reflect RBC aggregation. Employing human RBC–plasma suspensions exhibiting a wide range of aggregation, the present study examined relations between yield shear stress values and aggregation indices obtained using the Myrenne aggregometer: the latter approach uses a light-transmission technique and provides an “M” index at stasis and an “M1” at very low shear. Our results for normal controls and for angina patients without coronary artery disease indicate highly significant correlations (p<0.001) between the yield stress and both M and M1. Thus, within the range of aggregation studied, these findings lend support to the rheological validity of the Myrenne approach; extension of our findings to intensely aggregating RBC suspensions may require additional validation studies.
Keywords: Red cell aggregation, yield stress, Myrenne aggregometer, ESR
Journal: Biorheology, vol. 44, no. 1, pp. 29-35, 2007
