Vol. 279, Issue 1, R148-R151, July 2000
Brain-blood permeability: TNF-
promotes escape of protein
tracer from CSF to blood
Jodi B.
Dickstein1,
Harvey
Moldofsky1, and
John
B.
Hay2
1 Centre for Sleep and Chronobiology, 2 Departments
of Immunology and Laboratory Medicine and Pathobiology, University of
Toronto, Toronto, Ontario, Canada M5T 2S8
The objective of this study was to determine
the effect of tumor necrosis factor (TNF)-
on the efflux of protein
from the central nervous system to blood based on assessing the
clearance of radiolabeled albumin from the cerebrospinal fluid (CSF) to blood in rats. 125I-labeled human serum albumin
(125I-HSA) was injected into a lateral ventricle, and
venous blood was sampled hourly to determine the basal CSF protein
clearance into the blood. After this, rats were
intraventricularly infused with 10 µl TNF- and 10 µl
131I-HSA (n = 6) or 10 µl saline and 10 µl 131I-HSA (n = 6). Venous blood was
sampled hourly for 3 h. 131I-HSA tracer recovery
increased threefold in the venous blood and was significantly higher in
the spleen, muscles, and skin in animals treated with TNF-. No
significant changes were observed in control animals treated with
saline. The data suggest that TNF- promotes the clearance of protein
macromolecules from the CSF to the venous blood.
tumor necrosis factor-; cerebrospinal fluid; arachnoid villi
