title: Effects of sleep deprivation on pain-related factors in the temporomandibular joint.
abstract: BACKGROUND
  The objective of this study was to investigate the effects of experimental sleep deprivation (SD) on the temporomandibular joint (TMJ) in rats by examining pain-related factors and to determine the possible involvement of estrogen and NF (nuclear factor) κB signaling in the TMJ synovial membrane.
  
  
  METHODS
  The influence of SD, conducted in rats using the modified multiple platform method, was estimated by observing behavioral manifestations and examining changes in serum hormone levels. The morphologic changes of synovial tissue were observed with light microscopy and the serum levels of estrogen were measured by radioimmunoassay. Activation of NF-κB in the synovial membrane was examined using an immunofluorescence technique, and the expression levels of interleukin (IL) 1β, IL-6, tumor necrosis factor α, cyclooxygenase 2, and inducible nitric oxide synthase were measured with real-time polymerase chain reaction.
  
  
  RESULTS
  The SD group showed evidence of elevated anxiety and stress, and increased plasma levels of estradiol compared with the control group. The activity of NF-κB was significantly enhanced and translocation of NF-κB p65 was evident in the synovial membrane after SD. The expression of pain-related factors IL-1β, IL-6, cyclooxygenase-2, tumor necrosis factor α, and inducible nitric oxide synthase in the synovial membrane significantly increased after SD.
  
  
  CONCLUSIONS
  These results indicate that SD increases serum levels of estrogen and induces alterations in pain-related factors in the TMJ. The NF-κB pathway has been associated with the regulation of these inflammatory cytokines and plays an important role in temporomandibular disorders.
authors.affiliation: Department of Stomatology, Jinan General Military Hospital, Jinan, China.
authors.forename: Gaoyi
authors.initials: G
authors.lastname: Wu
authors.affiliation: Department of Orthodontics, Jinan Stomatological Hospital, Jinan, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Chen
authors.forename: Geng
authors.initials: G
authors.lastname: Wei
authors.affiliation: Department of Dental Implantology Centre, School of Stomatology, Capital Medical University, Beijing, China.
authors.forename: Gang
authors.initials: G
authors.lastname: Wei
authors.affiliation: Jinan Central Hospital Affiliated to Shandong University, Jinan, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Li
authors.affiliation: Department of Stomatology, Jinan General Military Hospital, Jinan, China. Electronic address: fmmugaoyi@hotmail.com.
authors.forename: Guoxiong
authors.initials: G
authors.lastname: Zhu
authors.affiliation: Department of Medical Genetics and Developmental Biology, and Department of Thoracic Surgery Tangdou Hospital, Fourth Military Medical University, Xi'an, China. Electronic address: dentist_effendi@yahoo.cn.
authors.forename: Zhengwei
authors.initials: Z
authors.lastname: Zhao
authors.affiliation: Department of Medical Genetics and Developmental Biology, and Department of Thoracic Surgery Tangdou Hospital, Fourth Military Medical University, Xi'an, China. Electronic address: 147148419@163.com.
authors.forename: Fei
authors.initials: F
authors.lastname: Huang
mesh_terms: D000818:Animals; D001007:Anxiety / Q000209:etiology / Q000378:metabolism; D001522:Behavior, Animal / Q000502:physiology; D051546:Cyclooxygenase 2 / Q000235:genetics / Q000378:metabolism; D004967:Estrogens / Q000378:metabolism; D005157:Facial Pain / Q000150:complications* / Q000378:metabolism; D005260:Female; D053583:Interleukin-1beta / Q000235:genetics / Q000378:metabolism; D015850:Interleukin-6 / Q000235:genetics / Q000378:metabolism; D016328:NF-kappa B / Q000378:metabolism; D052247:Nitric Oxide Synthase Type II / Q000235:genetics / Q000378:metabolism; D011897:Random Allocation; D017208:Rats, Wistar; D015398:Signal Transduction / Q000502:physiology; D012892:Sleep Deprivation / Q000150:complications* / Q000378:metabolism; D013312:Stress, Physiological / Q000502:physiology; D013583:Synovial Membrane / Q000378:metabolism; D013704:Temporomandibular Joint / Q000378:metabolism; D013705:Temporomandibular Joint Disorders / Q000150:complications* / Q000378:metabolism
chemical_list: D004967:Estrogens; D053583:Interleukin-1beta; D015850:Interleukin-6; D016328:NF-kappa B; D052247:Nitric Oxide Synthase Type II; C496318:Nos2 protein, rat; D051546:Cyclooxygenase 2
keywords: Estrogen; NF-κB; Pain; Sleep deprivation; Temporomandibular joint