Vol. 92, Issue 3, 1357-1362, March 2002
HIGHLIGHTED TOPICS
Functional Genomics of Sleep and Circadian
Rhythm
Selected Contribution: Circadian rhythm of
tumor necrosis factor-
uptake into mouse spinal cord
Weihong
Pan1,
Germaine
Cornélissen2,
Franz
Halberg2, and
Abba J.
Kastin1
1 Department of Medicine, Tulane University and the Veterans
Affairs Medical Center, New Orleans, Louisiana 70112-1262; and
2 Chronobiology Laboratories, University of Minnesota,
Minneapolis, Minnesota 55455
Circadian variations in the
actions of tumor necrosis factor-
(TNF-) have been observed.
Because a saturable transport system at the blood-brain barrier
mediates most of the influx of TNF- from blood to the central
nervous system (CNS), the circadian variation of the CNS effects of
TNF- could be related to changes in this transport system.
Accordingly, we measured the uptake of intravenously injected TNF-
into various CNS regions at different times and compared these
measurements with the uptake into a peripheral control (muscle). We
found that the spinal cord, but not the brain, showed a circadian
rhythm in the uptake of TNF-. This pattern is similar to that of
leptin but different from that of interleukin-1. The circadian rhythm
of the influx of TNF- into this region of the CNS suggests a
functional role for the spinal cord in the physiological actions of
TNF-.
blood-brain barrier; cytokine; transport
