title: Immunolocalization of AQP5 in resting and stimulated normal labial glands and in Sjögren's syndrome.
abstract: OBJECTIVE
  In our current work, in vivo examination of AQP5 distribution in labial salivary glands following stimulation of secretion has been carried out in normal individuals and in patients with Sjögren's syndrome.
  
  
  METHODS
  For this study, we selected five patients with primary Sjögren's syndrome (mean age 62.4 ± 10.6 s.d. years) diagnosed in accordance with the European Cooperative Community classification criteria. There were five patients (mean age 27 ± 2.5 s.d. years) in the control group. The subcellular distribution of AQP5 in human labial gland biopsies was determined with light and immunoelectron microscopy before and 30 min after administration of oral pilocarpine.
  
  
  RESULTS
  In unstimulated control and Sjögren's labial glands, AQP5 is about 90% localized in the apical plasma membrane, with only rarely associated gold particles with intracellular membrane structures. We have found no evidence of pilocarpine-induced changes in localization of AQP5 in either healthy individuals or patients with Sjögren's syndrome.
  
  
  CONCLUSIONS
  Our studies indicate that neither Sjögren's syndrome itself, nor muscarinic cholinergic stimulation in vivo caused any significant changes in the distribution of AQP5 in the labial salivary gland cells.
authors.affiliation: Department of Oral Diagnostics, Semmelweis University, Budapest, Hungary.
authors.forename: V
authors.initials: V
authors.lastname: Gresz
authors.forename: A
authors.initials: A
authors.lastname: Horvath
authors.forename: I
authors.initials: I
authors.lastname: Gera
authors.forename: S
authors.initials: S
authors.lastname: Nielsen
authors.forename: T
authors.initials: T
authors.lastname: Zelles
mesh_terms: D000328:Adult; D000368:Aged; D051402:Aquaporin 5 / Q000378:metabolism*; D001706:Biopsy; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D016253:Microscopy, Immunoelectron; D008875:Middle Aged; D010862:Pilocarpine / Q000494:pharmacology; D012469:Salivary Glands / Q000187:drug effects / Q000378:metabolism / Q000473:pathology / Q000502:physiology* / Q000503:physiopathology; D012859:Sjogren's Syndrome / Q000473:pathology / Q000503:physiopathology*; D013347:Subcellular Fractions / Q000378:metabolism
chemical_list: C496036:AQP5 protein, human; D051402:Aquaporin 5; D010862:Pilocarpine
keywords: Sjögren's syndrome; aquaporin-5; oral pilocarpine; salivary secretion