Shear rate and orientation of erythrocytes in pulmonary microvessels of bullfrogs

Issue title: Special Issue for the Conference Proceedings Euromech 186. Part I. Nancy, France, 17–19 September 1984

Guest editors: M. Lucius and J.F. Stoltz

Article type: Research Article

Authors: Koyama, T.

Affiliations: Research Institute of Applied Electricity, Hokkaido University, 060 Sapporo, Japan

Note: [] Accepted by: Guest Editor J.F. Stoltz

Abstract: Wall shear rates in arterioles and capillaries in the surface of exposed bull frog lung were estimated to be 436 and 975 sec−1, respectively, at the intra-lung pressure at which a maximum flow velocity was observed. These high shear rates will probably permit an orientation of erythrocytes in a high degree. An orientation of erythrocytes was confirmed at a wall shear rate smaller than 16 sec−1 by means of a microscope connected with a video camera system. Erythrocytes kept their long axis along the direction of the overall blood flow, even when the blood flow transiently stopped flowing during the diastolic phase. The orientation of erythrocytes in such a high degree will be effective to reduce the blood flow resistance in pulmonary microvessels.

Keywords: microvessels, Frog lung, wall shear rate, shear stress, orientation of erythrocytes

DOI: 10.3233/BIR-1985-22502

Journal: Biorheology, vol. 22, no. 5, pp. 379-384, 1985