Blood, 1958, Vol. 13, No. 2, pp. 177-191.
© 1958 American Society of Hematology, Inc.
Platelet Adsorptive Properties and Platelet Extracts
in Thromboplastin Generation
SEYMOUR PERRY 1 and
CHARLES G. CRADDOCK JR. 1
1 Department of Medicine, School of Medicine, University of California Medical
Center and Wadsworth Veterans Administration Center, Los Angeles, California.
(1) Simple incubation of normal platelets in saline for 10 minutes at 37 C.
markedly diminishes their activity in the thromboplastin generation test. This
loss of activity is due to the removel of a factor(s) from the platelet and is
present in the saline extract.
(2) These "attenuated" platelets retain their effect on the recalcification
time, prothrombin consumption, and clotting time of whole blood.
(3) Attenuated platelets, as well as platelets thought to be qualitatively
defective, regain normal activity in the TGT after incubation in normal plasma
or in plasmas from patients with qualitative platelet defects.
(4) Attenuated platelets, in contrast to qualitatively defective platelets, are
restored to normal, as measured by the TGT, after treatment with saline extracts of normal platelets. Attenuated platelets, however, do not function normally after incubation with saline extracts of qualitatively defective platelets.
(5) The possible mechanisms involved are discussed, and it is concluded
that the phenomenon involves the adsorption of plasma factor(s) by the platelet. The nature of the plasma factor(s) is not known.
Submitted on June 25, 1957
Accepted on September 15, 1957
