The reduction of voluntary physical activity after poly I:C injection is independent of the effect of poly I:C-induced interferon-beta in mice.
One characteristic of sickness behavior in mice is demonstrated by a reduction in voluntary wheel-running activity during infection. Among synthetic double-stranded (ds) RNAs, polyriboinosinic: polyribocytidylic acid (poly I:C) activates to produce interferon (IFN) -beta, which plays an important role in anti-viral activity and host-defense. However, how voluntary wheel-running activity is regulated during poly I:C infection is unknown. To determine whether poly I:C-induced IFN-beta production is responsible for reduced spontaneous physical activity, we measured poly I:C-induced changes in voluntary wheel-running activity in mice. In this experiment, the mice were injected with poly I:C (0-5 mg/kg i.v.) and/or anti-IFN-beta neutralizing antibody (1.5x10(5) U/kg i.v.). We also observed the direct effect of injection of recombinant IFN-beta (rIFN-beta: 5.0x10(4) and 2.5x10(5) U/kg) on wheel-running behavior. Poly I:C treatment dose-dependently reduced wheel-running activity, and induced an increase in plasma IFN-beta in mice. However the activity was not attenuated by the neutralizing antibody specific to IFN-beta treatment. Additionally, the wheel-running activity in rIFN-beta treated mice was maintained, although they showed a higher IFN-gamma inducible protein (IP)-10 concentration in plasma compared with that of the vehicle group. Our results suggest that the transient reduction in physical activity after poly I:C injection is induced dose dependently, but that the mediator might not be poly I:C-induced IFN-beta.
Matsumoto
Takashi
T
Department of Health and Sports Science, Kawasaki University of Medical Welfare, 288 Matsushima Kurashiki, Okayama 701-0193, Japan.
Takahashi
Hiroshi
H
Shiva
Daisuke
D
Kawanishi
Noriaki
N
Kremenik
Michael J
MJ
Kato
Yasuko
Y
Yano
Hiromi
H
D000704:Analysis of Variance; D000818:Animals; D000906:Antibodies / Q000494:pharmacology; D001522:Behavior, Animal / Q000187:drug effects; D001835:Body Weight / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004347:Drug Interactions; D004435:Eating / Q000187:drug effects; D007155:Immunologic Factors / Q000008:administration & dosage*; D007369:Interferon Inducers / Q000494:pharmacology*; D007370:Interferon Type I / Q000494:pharmacology; D016899:Interferon-beta / Q000276:immunology / Q000494:pharmacology*; D007371:Interferon-gamma / Q000097:blood; D008297:Male; D051379:Mice; D009043:Motor Activity / Q000187:drug effects*; D011070:Poly I-C / Q000494:pharmacology*; D011994:Recombinant Proteins
D000906:Antibodies; D007155:Immunologic Factors; D007369:Interferon Inducers; D007370:Interferon Type I; D011994:Recombinant Proteins; D016899:Interferon-beta; D007371:Interferon-gamma; D011070:Poly I-C