FUNDAMENTAL LAWS OF THE DEFORMATIONAL
BEHAVIOR OF ERYTHROCYTES IN SHEAR FLOW

N. N. Firsov,a A. V. Priezzhev,b 
N. V. Klimova,a  and A. Yu. Tyurinab 

UDC 577.353:567.322

The dependences of the deformability parameter of erythrocytes 
on the shear stress in the Couette flow upon a change in their membrane 
rigidity or internal-content viscosity have been investigated by the 
diffractometric (ectacytometric) method. The results obtained suggest 
that the yield stress of cells measured by this method reflects the 
deformability of erythrocyte membranes, and the slope of the deformation 
curve rectified in the semilogarithmic coordinate system depends on 
the viscosity of the internal content of the cell. A parameter such 
as the limit deformation of erythrocytes is primarily determined by 
the viscosity of the membrane cytoskeleton.

aRussian State Medical University, 1, Ostrovityanov Str., Moscow, 
117997, Russia; bM. V. Lomonosov Moscow State University, 1, 
Vorobiyovy Gory, Moscow, Russia. Translated from Inzhenerno-Fizicheskii 
Zhurnal, Vol. 79, No. 1, pp. 114-120, January-February, 2006. Original 
article submitted November 23, 2004.