Trigeminal c-Fos expression and behavioral responses to pulpal inflammation in ferrets

Siriporn Chaisin Chattipakorn, Asgeir Sigurdsson, Alan R. Light, Matti Narhi, William Maixner

Research output: Contribution to journalArticle

Abstract

Injury to peripheral dental tissues evokes dynamic alternations in central sensory pathways. We have previously reported that transient stimulation of the dental pulp with noxious heat evokes the induction of the immediate early gene product Fos in the transitional region between subnucleus interpolaris and caudalis (Vi/Vc) and subnucleus caudalis (Vc). A question arises as to whether similar changes occur in response to inflammation to the tooth pulp. In this study, the effects of pulpal inflammation produced by bacterial lipopolysaccharide (LPS) on face-grooming behavior and trigeminal Fos expression were examined. Face-grooming behaviors were recorded daily for 3 days pre- and 24, 48 and 72 h post- LPS or saline application. All animals were perfused 72 h post- LPS or saline application. Brainstems were processed for Fos-like immunoreactivity (Fos-LI). Teeth were processed for H&E staining. Histological examination of LPS-treated teeth revealed features of an acute pulpitis. Moreover, LPS-treated animals showed greater face-grooming activity (i.e. tongue protrusions) directed to the injured tooth than the sham-operated group. The number of Fos-positive neurons was greater in the trigeminal subnucleus caudalis (Vc) and the transitional regions (Vi/Vc) in LPS-treated animals compared with sham-operated animals, and greater in the deeper laminae than the superficial laminae of each trigeminal region. LPS treatment did not evoke Fos expression in the rostral trigeminal regions above Vi/Vc. These results demonstrate that LPS-induced pulpal inflammation results in significant alterations in the Vi/Vc and Vc, and such changes may underlie the observed nociceptive behavioral responses and may play an important role in producing a symptomatic pulpitis in humans.

Original languageEnglish (US)
Pages (from-to)61-69
Number of pages9
JournalPain
Volume99
Issue number1-2
DOIs
StatePublished - Sep 2002

Keywords

  • Behavioral response
  • Lipopolysaccharide
  • Pulpal inflammation
  • Subnucleus caudalis
  • Subnucleus interpolaris
  • Tooth pulp
  • Trigeminal c-Fos expression

ASJC Scopus subject areas

  • Neurology
  • Clinical Neurology
  • Anesthesiology and Pain Medicine

Fingerprint Dive into the research topics of 'Trigeminal c-Fos expression and behavioral responses to pulpal inflammation in ferrets'. Together they form a unique fingerprint.

  • Cite this