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The influence of erythrocyte shape on suspension viscosities
Author(s) -
REINHART W. H.,
SINGHMARCHETTI M.,
STRAUB P. W.
Publication year - 1992
Publication title -
european journal of clinical investigation
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.164
H-Index - 107
eISSN - 1365-2362
pISSN - 0014-2972
DOI - 10.1111/j.1365-2362.1992.tb01933.x
Subject(s) - viscosity , tonicity , dextran , chemistry , echinocyte , relative viscosity , syneresis , blood viscosity , suspension (topology) , reduced viscosity , biophysics , apparent viscosity , shear rate , erythrocyte aggregation , chromatography , erythrocyte deformability , red blood cell , materials science , biochemistry , biology , composite material , medicine , mathematics , homotopy , pure mathematics , fibrinogen
. Erythrocyte shape changes are known to occur in vivo and can readily be induced in vitro . We have analysed the influence of increasing stomatocyto‐sis produced by 0–0.64 mmol 1 ‐1 chlorpromazine and increasing echinocytosis induced with 0–120 mmol 1 ‐1 salicylate or 0–8 mmol 1 ‐1 2,4‐dinitrophenol on suspension viscosities. The morphological index of each sample was determined and related to the suspension viscosity. It was found that the viscosity was increased by echinocytosis in dextran‐free solutions, where no aggregation occurred. The viscosity could be normalized by retransforming echinocytes into discocytes. Under conditions with erythrocyte aggregation (suspension with 4 g dl ‐1 dextran 70, low shear rate:0.1 s ‐1 ) a small degree of echinocytosis produced the highest viscosity, whereas at higher degrees of echinocytosis the ability to aggregate was reduced and the viscosity was similar to that of discocytes or stomato‐cytes. Erythrocytes incubated in hypotonic medium (constant cell number/volume) had a higher viscosity than cells in iso‐ or hypertonic medium. Severely hypotonic medium led to sphering of erythrocytes which reduced the ability of these cells to aggregate and hence decreased the viscosity of suspensions with dextran at low shear rate. The results indicate that discocytes have the lowest viscosity and thus the best oxygen transport efficiency and that iso‐ to hypertoni‐city provides a lower viscosity and better oxygen transport efficiency than hypotonicity. These results may contribute to the understanding of blood flow in health and disease.