Flow-induced detachment of adherent platelets undergoing
morphological changes on fibrinogen-coated surface.
Jen, Chauying J., Hui-Mei Li, Jong-Shyan Wang, Hsiun-Ing Chen, and
Shunichi Usami.
Department of Physiology, National Cheng -Kung University Medical
College, Tainan, Taiwan, Rep. of China, Institute of Biomedical
Sciences, Academia Sinica, Taipei, Taiwan, Rep. of China
APStracts 2:0292H, 1995.
A study of the shear forces under which adherent platelets of
different morphology can be detached from surfaces was carried out
using a newly designed tapered flow chamber, which covered the entire
shear range of physiological circulation. Platelets naturally settled
on a fibrinogen-coated surface were exposed to shear flow and
subsequently processed for scanning electron microscopic observation.
We found that 1) the density of remaining platelets after flow
exposure decreased with local shear stress; 2) adherent platelets of
different morphology withstood different levels of shear stress, most
round cells and 40% of cells that had a few short pseudopods were
detached at < 10 dyne/cm2, while most spread cells could
withstand 50 dyne/cm2; 3) pulsatile flow was more effective in
removing adherent platelets than equivalent steady flow was; 4)
cytochalasin D and colchicine retarded platelet shape change and made
them easier to be detached by shear forces; 5) metabolic energy
-depleted platelets spread readily and formed shear-resistant clumps.
Our observations indicated that adherent platelets of different
morphology on fibrinogen-coated surface could withstand different
levels of flow shear stress.
Received 27 December 1994; accepted in final form 19 June 1995.
APS Manuscript Number H1135-4.
Article publication pending Am. J. Physiol. (Heart Circ. Physiology).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 18 July 1995.