Blood, 1967, Vol. 29, No. 3, pp. 341-353.
© 1967 American Society of Hematology, Inc.
The Relation of Blood Platelet Survival and Distribution
to 14C-Serotonin Distribution and Excretion
R. M. HEYSSEL 1,
L. J. SILVER 1,
MARIE WASSON 1, and
A. B. BRILL 1
1 Divisions of Nuclear Medicine and Biophysics and Hematology of the Department of Medicine, Vanderbilt University School of Medicine, Nashville, Tenn.
1. The distribution of 14C-5-HT following infusion is different from that of
endogenous serotonin. One hour after infusion it is, in major part, a function
of the distribution of blood platelets.
2. The spleen in rats is the site of a pool of platelets. Based on both 14C
and platelet recovery data in normal and splenectomized animals, this pool
approximates 40 per cent of the total circulating platelets.
3. Postsplenectomy thrombocytosis may relate to removal of a platelet reservoir with shift of the platelets normally contained therein to the peripheral
circulation.
4. The shape of platelet survival curves in rats is neither strictly linear nor
curvilinear but normally is determined primarily by age-related processes in
the platelet. Platelet survival curves tend to become curvilinear in thrombocytopenic animals, indicating that there is probably an additional small, fixed
random loss of platelets from the circulation.
5. The disappearance of 14C-5-HT from blood platelets approximates but is
not completely representative of the disappearance of the platelets themselves.
It is probable that elution from platelets and possibly reutilization of platelet
label occurs.
Submitted on May 27, 1966
Accepted on September 21, 1966
