Diurnal variations of tumor necrosis factor alpha mRNA and alpha-tubulin mRNA in rat brain.
The experiments described herein were designed to determine whether tumor necrosis factor alpha (TNF-alpha) displays a diurnal variation in various areas of the normal rat brain. TNF-alpha mRNA transcripts were detected by reverse-transcriptase polymerase chain reaction. To monitor diurnal changes in TNF-alpha and alpha-tubulin expression, rats were sacrificed every 4 h for 24 h starting 1 h after light onset; relative mRNA levels were determined for the cerebellum, cortex, hippocampus, hypothalamus and brainstem. TNF-alpha mRNA was higher during the light than in the dark phase in the hypothalamus and hippocampus. alpha-Tubulin mRNA exhibited a similar diurnal variation in the hypothalamus, hippocampus and cortex. In contrast, beta-actin mRNA was lower during the light phase than the dark phase in the hippocampus and cortex. The observed diurnal variations in TNF-alpha mRNA are consistent with the hypothesis that TNF has a physiological role in the brain.
Bredow
S
S
Department of Physiology and Biophysics, University of Tennessee, Memphis, USA.
Guha-Thakurta
N
N
Taishi
P
P
Obál
F
F
Krueger
J M
JM
D000818:Animals; D001923:Brain Chemistry / Q000502:physiology*; D002940:Circadian Rhythm / Q000502:physiology*; D008297:Male; D012333:RNA, Messenger / Q000032:analysis / Q000096:biosynthesis*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012890:Sleep / Q000502:physiology; D014404:Tubulin / Q000235:genetics*; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics*
D012333:RNA, Messenger; D014404:Tubulin; D014409:Tumor Necrosis Factor-alpha