Prostacyclin production by perturbed bovine aortic endothelial cells in
culture
PP Nawroth, DM Stern, KL Kaplan and HL Nossel
This study reports that endotoxin (Escherichia coli serotype 026:B6) and
12-O-tetradecanoyl-phorbol-13-acetate stimulate cultured bovine aortic
endothelial cells to generate prostacyclin. The prostacyclin concentration
of the culture medium was measured indirectly by radioimmunoassay for
6-keto-PGF1 alpha. The amount of prostacyclin generated depended on the
concentration of endotoxin or phorbol diester. Prostacyclin generation was
not immediate, but occurred slowly after a six-hour lag period. The
perturbed cells contracted and showed marked shape changes that correlated
temporally with the start of enhanced prostacyclin production.
Cytochalasins B and D, vinblastine, and colchicine inhibited prostacyclin
production, indicating involvement of the cytoskeleton in the cellular
response to endotoxin and phorbol diester. The increase in prostacyclin
production was prevented by trifluoperazine, an inhibitor of the
Ca++-calmodulin system, which is known to be involved in cytoskeletal
function. Generation of prostacyclin was inhibited by cycloheximide and
actinomycin D, indicating dependence on protein and ribonucleic acid
synthesis. It is postulated that exposure to endotoxin or phorbol diester
leads, via a series of reactions that involve RNA and protein synthesis and
require intact cytoskeletal function, to the generation of toxic active
intermediate(s) that stimulate the enzymes necessary for prostacyclin
production.
Volume 64,
Issue 4,
pp. 801-806,
10/01/1984
Copyright © 1984 by The American Society of Hematology
