title: Lipopolysaccharide-induced pulpitis up-regulates TRPV1 in trigeminal ganglia.
abstract: Tooth pain often accompanies pulpitis. Accumulation of lipopolysaccharides (LPS), a product of Gram-negative bacteria, is associated with painful clinical symptoms. However, the mechanisms underlying LPS-induced tooth pain are not clearly understood. TRPV1 is a capsaicin- and heat-gated nociceptive ion channel implicated in thermosensation and hyperalgesia under inflammation or injury. Although TRPV1 is expressed in pulpal afferents, it is not known whether the application of LPS to teeth modulates TRPV1 in trigeminal nociceptors. By assessing the levels of protein and transcript of TRPV1 in mouse trigeminal ganglia, we demonstrate that dentinal application of LPS increases the expression of TRPV1. Our results suggest that the up-regulation of TRPV1 in trigeminal nociceptors following bacterial infection could contribute to hyperalgesia under pulpitis conditions.
authors.affiliation: University of Maryland Baltimore School of Dentistry, Program in Neuroscience, Department of Neural and Pain Sciences, 650 W. Baltimore Street, Baltimore, MD 21201, USA. mchung@umaryland.edu
authors.forename: M-K
authors.initials: MK
authors.lastname: Chung
authors.forename: J
authors.initials: J
authors.lastname: Lee
authors.forename: G
authors.initials: G
authors.lastname: Duraes
authors.forename: J Y
authors.initials: JY
authors.lastname: Ro
mesh_terms: D000818:Animals; D015153:Blotting, Western; D002211:Capsaicin / Q000494:pharmacology; D003807:Dentin Sensitivity / Q000209:etiology / Q000378:metabolism*; D057809:HEK293 Cells; D006801:Humans; D008070:Lipopolysaccharides; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D009619:Nociceptors / Q000187:drug effects / Q000378:metabolism; D011671:Pulpitis / Q000150:complications / Q000378:metabolism*; D050916:TRPV Cation Channels / Q000096:biosynthesis*; D014098:Toothache / Q000209:etiology / Q000378:metabolism*; D012668:Trigeminal Ganglion / Q000166:cytology / Q000378:metabolism*; D015854:Up-Regulation
chemical_list: D008070:Lipopolysaccharides; D050916:TRPV Cation Channels; C494482:TRPV1 protein, human; D002211:Capsaicin