title: Posterior insular molecular changes in myofascial pain.
abstract: Temporomandibular disorders (TMD) include craniocervical pain conditions with unclear etiologies. Central changes are suspected; however, few neuroimaging studies of TMD exist. Single-voxel proton magnetic resonance spectroscopy ((1)H-MRS) was used before and after pressure-pain testing to assess glutamate (Glu), glutamine (Gln), N-acetylaspartate (NAA), and choline (Cho) levels in the right and left posterior insulae of 11 individuals with myofascial TMD and 11 matched control individuals. Glu levels were significantly lower in all individuals after pain testing. Among those with TMD, left-insular Gln levels were related to reported pain, left posterior insular NAA and Cho levels were significantly higher at baseline than in control individuals, and NAA levels were significantly correlated with pain-symptom duration, suggesting adaptive changes. The results suggest that significant central cellular and molecular changes can occur in individuals with TMD.
authors.affiliation: Department of Biologic and Materials Sciences, School of Dentistry, 1011 N. University Ave., University of Michigan, Ann Arbor, MI 48109-1078, USA. geger@umich.edu
authors.forename: G E
authors.initials: GE
authors.lastname: Gerstner
authors.forename: R H
authors.initials: RH
authors.lastname: Gracely
authors.forename: A
authors.initials: A
authors.lastname: Deebajah
authors.forename: E
authors.initials: E
authors.lastname: Ichesco
authors.forename: A
authors.initials: A
authors.lastname: Quintero
authors.forename: D J
authors.initials: DJ
authors.lastname: Clauw
authors.forename: P C
authors.initials: PC
authors.lastname: Sundgren
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D001224:Aspartic Acid / Q000031:analogs & derivatives / Q000032:analysis; D001923:Brain Chemistry; D016022:Case-Control Studies; D002540:Cerebral Cortex / Q000378:metabolism*; D002794:Choline / Q000032:analysis; D005157:Facial Pain / Q000378:metabolism*; D005260:Female; D018698:Glutamic Acid / Q000032:analysis; D005973:Glutamine / Q000032:analysis; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D059906:Neuroimaging / Q000379:methods; D010147:Pain Measurement; D017288:Pain Threshold; D013706:Temporomandibular Joint Dysfunction Syndrome / Q000378:metabolism*; D055815:Young Adult
chemical_list: D005973:Glutamine; D001224:Aspartic Acid; D018698:Glutamic Acid; C000179:N-acetylaspartate; D002794:Choline