Brain interleukin-1 is involved in blood interleukin-6 response to immobilization stress in rats.
Interleukin (IL)-6, a cytokine for host defense responses to infection and inflammation, is known to be induced by non-invasive physical or psychological stress, too. To test possible involvement of brain IL-1 in the stress-induced IL-6 production, IL-1 mRNA expression in the hypothalamus, in parallel with blood IL-6 level, was examined in rats subjected to restriction of their movement (immobilization stress). When rats were immobilized, the hypothalamic IL-1 beta mRNA level was increased in 1 hr, followed by progressive rises in the serum IL-6 level. The immobilization-induced rise in serum IL-6 was mimicked by intracerebroventricular (icv) administration of IL-1 beta under normal conditions, whereas it was attenuated by icv injection of an IL-1 receptor antagonist. These results indicate that IL-1 in the hypothalamus plays a pivotal mediating role in the stress-induced peripheral IL-6 production.
Ishikawa
I
I
Laboratory of Biochemistry, Department of Biomedical Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo 060-0818, Japan.
Kitamura
H
H
Kimura
K
K
Saito
M
M
D000818:Animals; D015139:Blotting, Southern / Q000662:veterinary; D001921:Brain / Q000378:metabolism*; D007031:Hypothalamus / Q000378:metabolism; D007276:Injections, Intraventricular / Q000662:veterinary; D007375:Interleukin-1 / Q000502:physiology*; D015850:Interleukin-6 / Q000097:blood*; D008297:Male; D051381:Rats; D017472:Receptors, Interleukin-1 / Q000037:antagonists & inhibitors; D012149:Restraint, Physical / Q000662:veterinary; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000662:veterinary; D013312:Stress, Physiological / Q000097:blood / Q000662:veterinary*
D007375:Interleukin-1; D015850:Interleukin-6; D017472:Receptors, Interleukin-1