抄録
Platelets in whole blood from 7 healthy subjects were studied serially under scanning electron microscopy (SEM) and light microscopy (LM) to evaluate their morphological changes during their activation as exactly as possible. No drugs (anticoagulants) were used in sampling blood in this study.
1. Needle-shaped particles (0.7×0.2μm) immediately appeared on OCS and around the platelets in all subjects, but disappeared shortly. These particles were coloured by May-Giemsa stain, and they were conidered to be protein. The serial changes in their morphology and other properties suggested that they were derived from alphagranules. From these findings, the rapid release from alphagranules was considered to occur during activation of unstimulated platelets.
2. After the appearance of the needle-shaped particles, spherical particles 0.1-0.3μm in diameter were observed on platelets and fibrin fibers in experiment (2). Moreover, marked accumulation of microparticles was observed around platelets experiment (1) after the appearance of the fibrin net.
