Complex viscoelasticity of normal and lectin treated erythrocytes using laser diffractometry

A new method to find directly complex viscoelastic parameters (CVP) of red blood cells (RBC) is presented in this paper. Experimental determinations w ere carried out in an Erythrodeformeter (Rasia et al., 1986) operating in o scillating mode (0.5 to 3.5 Hz). The Erythrodeformeter performs direct dete rmination of CVP of erythrocytes undergoing sinusoidal shear stresses by la ser diffractometry. The measurements lead to the determination of mean valu es of the four components of erythrocyte complex viscoelasticity. The influ ence of the alterations induced on erythrocyte membrane by vegetable lectin s (Ulex europaeus, wheat germ agglutinin and Enterolobium contorticilicum s eeds) was analyzed to verify the sensitivity of this method. Differences ob served between the CVP parameters of treated cells and the ones correspondi ng to control samples (non treated cells) are analyzed. Results obtained fr om cells treated with wheat germ agglutinin agree with observations publish ed by Smith and Hochmuth (1982). Determinations of RBC complex viscoelastic ity carried out by laser diffractometry could become an important tool to u nderstand the influence of the factors associated with alterations of the t heologic properties of RBC membrane, which can affect the in vivo blood flo w.