Related Experiment Video
Updated: Aug 11, 2026

Micro-particle Image Velocimetry for Velocity Profile Measurements of Micro Blood Flows
Published on: April 25, 2013
Motion of red blood cells in capillaries with variable cross-sections
1Department of Physiology, University of Arizona, Tucson 85724, USA.
Abstract:
Red blood cells undergo continual deformation when traversing microvessels in living tissues. This may contribute to higher resistance to blood flow observed in living microvessels, compared with that in corresponding uniform glass tubes. We use a theoretical model to simulate single-file motion of red cells though capillaries with variable cross-sections, assuming axisymmetric geometry. Effects of cell membrane shear viscosity and elasticity are included, but bending resistance is neglected. Lubrication theory is used to describe the flow of surrounding plasma. When a red cell encounters a region of capillary narrowing, additional energy is dissipated, due to membrane viscosity, and due to narrowing of the lubrication layer, increasing the flow resistance. Predicted resistance to cell motion in a vessel with periodic constrictions (diameter varying between 5 microns and 4 microns) is roughly twice that in a uniform vessel with diameter 4.5 microns. Effects of transient red cell deformations may contribute significantly to blood flow resistance in living microvessels.
Related Concept Videos
Blood Flow
Structure of Blood Vessels
Capillaries and Their Types
Capillary Beds
Capillaries connect arterioles, small branches of arteries, to venules,...
Autoregulation of Blood Flow
Chemical Signaling in Autoregulation
Chemical signaling operates at the precapillary sphincter level, inciting either contraction or relaxation.
Applications of Integration to Find Blood Flow

