Proplatelets and stress platelets
M Tong, P Seth and DG Penington
The process of platelet formation by the fragmentation of megakaryocyte
pseudopodia, termed proplatelets, demonstrable in the marrow sinusoids is
poorly understood. "Stress" platelets produced under conditions of
stimulated platelet production differ from normal circulating platelets
with respect to volume and a number of functional characteristics. To
clarify the relationship of stress platelets to proplatelets, rats were
injected with heterologous platelet antiserum. Nondiscoid platelet forms,
some characteristically beaded in appearance, strongly resembling bone
marrow proplatelets, can be recovered in the circulation of normal rats.
During the early period of recovery from acute thrombocytopenia, there was
a substantial increase in the proportion of these elongated platelets in
the citrated platelet rich plasma. Exposure to EDTA rendered them
spherical. Circulating proplatelets may contribute significantly to the
prompt increase in platelet volume during recovery from acute
thrombocytopenia at a time prior to significant increase in megakaryocyte
size and ploidy.
Volume 69,
Issue 2,
pp. 522-528,
02/01/1987
Copyright © 1987 by The American Society of Hematology
