Expression of c-fos-like protein in the rat brain after injection of interleukin-1-beta into the gingiva.
Expression of the c-fos proto-oncogene in the rat brain was examined by immunostaining for fos, the nuclear protein product of the c-fos gene, after injection of interleukin-1-beta (IL-1 beta) into the gingiva of an incisor. The distribution pattern of labelled cells was compared with that induced by tooth pulp stimulation. Neurons that express fos-immunoreactivity (fos-IR) appeared in several regions in the neuraxis 1.5 h after IL-1 beta injection, peaked at 2 h, and then declined. Labelled cells were found bilaterally in regions that contribute to pain-relay and pain-inhibition. The distribution of labelled cells almost matched the pattern induced by noxious tooth pulp stimulation. In indomethacin-pretreated animals, no neurons expressing fos-IR were found in nuclei associated with relay of nociception nor in nuclei contributing to inhibition of nociception. The results suggest that a small amount of IL-1 beta at the site of periodontal disease can induce fos-IR in brain neurons through increased prostaglandin production.
Hamba
M
M
Department of Physiology, Showa University, School of Dentistry, Tokyo, Japan.
Muro
M
M
Hiraide
T
T
Ozawa
H
H
D000818:Animals; D001921:Brain / Q000378:metabolism*; D003782:Dental Pulp / Q000502:physiology; D004558:Electric Stimulation; D005260:Female; D005881:Gingiva / Q000502:physiology*; D007150:Immunohistochemistry; D007213:Indomethacin / Q000494:pharmacology; D007267:Injections; D007375:Interleukin-1 / Q000008:administration & dosage* / Q000494:pharmacology; D010146:Pain / Q000503:physiopathology; D016760:Proto-Oncogene Proteins c-fos / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D014018:Tissue Distribution
D007375:Interleukin-1; D016760:Proto-Oncogene Proteins c-fos; D007213:Indomethacin