title: Expression and localization of aquaporin-1 in temporomandibular joint disc with internal derangement.
abstract: BACKGROUND
  Internal derangement is the most frequent arthropathy affecting the temporomandibular joint, where its commonest form is anterior disc displacement with or without reduction. Despite the frequency of the disorder, the biochemical features of displaced discs are still unclear.
  
  
  METHODS
  We investigated the expression pattern and localization of aquaporin-1, an important channel protein involved in plasma membrane water permeability, in patients with anterior disc displacement (both with and without reduction), with a view to assessing the characteristics of local tissue responses to the microenvironmental changes induced by abnormal mechanical loading of the displaced disc. Protein expression was studied by immunohistochemistry in different areas of discs from 18 patients with anterior disc displacement with or without reduction and in four normal controls.
  
  
  RESULTS
  A greater proportion of cells immunopositive for aquaporin-1 were detected in diseased than in normal discs. Whereas protein expression was substantially similar in the different areas of normal discs, a significantly larger number of immunopositive cells were detected in the posterior band of displaced discs without reduction and in the anterior and intermediate bands of those with reduction.
  
  
  CONCLUSIONS
  These findings suggest that aquaporin-1 is expressed and upregulated in temporomandibular joint with anterior disc displacement (both with and without reduction).
authors.affiliation: Department of Bio-Medical Sciences, University of Catania, Catania, Italy. carla.loreto@unict.it
authors.forename: Carla
authors.initials: C
authors.lastname: Loreto
authors.forename: Concetta
authors.initials: C
authors.lastname: Galanti
authors.forename: Luis Eduardo
authors.initials: LE
authors.lastname: Almeida
authors.forename: Rosalia
authors.initials: R
authors.lastname: Leonardi
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Pannone
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Musumeci
authors.forename: Maria Luisa
authors.initials: ML
authors.lastname: Carnazza
authors.forename: Rosario
authors.initials: R
authors.lastname: Caltabiano
mesh_terms: D000328:Adult; D051398:Aquaporin 1 / Q000032:analysis*; D001696:Biomechanical Phenomena; D002102:Cadaver; D060833:Cellular Microenvironment; D019902:Chondrocytes / Q000473:pathology; D003094:Collagen / Q000032:analysis; D005157:Facial Pain / Q000145:classification; D005260:Female; D005347:Fibroblasts / Q000473:pathology; D006801:Humans; D004204:Joint Dislocations / Q000145:classification / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D010147:Pain Measurement; D011312:Pressure; D013314:Stress, Mechanical; D019224:Temporomandibular Joint Disc / Q000473:pathology*; D013705:Temporomandibular Joint Disorders / Q000145:classification / Q000473:pathology*; D055815:Young Adult
chemical_list: C496020:AQP1 protein, human; D051398:Aquaporin 1; D003094:Collagen