Semin Thromb Hemost 1995; 21(2): 119-122
DOI: 10.1055/s-2007-1000385
Copyright © 1995 by Thieme Medical Publishers, Inc.

Ultrastructural Aspects of Platelet Adhesion on Subendothelial Structures

Andreas Ruf, Eberhard Morgenstern
  • From the Medizinische Biologie, Universitaet des Saarlandes, D-66421 Homburg and Klinikum Karlsruhe, Medizinisch-Diagnostisches Institut, D-76133 Karlsruhe, Germany
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Publication History

Publication Date:
06 February 2008 (online)

Abstract

Platelet adhesion to ligands within the subendothelium induces platelet activation. Ultrastructural and immunocytochemical investigations were carried out to obtain information on the microtopography of the adhesive interactions. Rabbit platelets which react in vivo with endothelial lesions (V. jugularis), and human platelets which react in vitro with collagen were observed. It was shown that the reaction of adhering platelets depends on the microtopography of the adhesive surface 1. On plane surfaces the platelets spread 2. Collagen fibers induce the formation of focal contacts. They are initiated by binding of ligands to certain transmembrane receptors. The contact mediates the formation of the contractile gel, which acts as a constricting sphere internalizing surface bound ligands, i.e., retraction of collagen networks. Most of the experiments hitherto dealt with platelets that spread. The described findings show that the reaction mentioned above plays a more important role than previously imagined and may be the physiological response of platelets interacting with subendothelial components in vessel lesions.

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