title: Apoptosis and expression of AQP5 and TGF-beta in the irradiated rat submandibular gland.
abstract: OBJECTIVE
  To evaluate the effect of X-ray irradiation on apoptosis and change of expression of aquaporin 5 (AQP5) and transforming growth factor-β(TGF-β) in the rat submandibular gland (SMG).
  
  
  METHODS
  SMGs of 120 male Sprague-Dawley rats were irradiated with a single X-ray dose (3, 10, 20, or 30 Gy). At the early and late post-irradiation phase, apoptosis was measured by the terminal deoxynucleotidyl transferase biotin-dUTP nick end labeling (TUNEL) method, and expression of AQP5 and TGF-β was determined by immunohistochemical staining.
  
  
  RESULTS
  At the late post-irradiation phase, increased apoptosis was evident and marked decreases of expression of AQP5 expression by acinar cells and TGF-β expression by ductal cells were evident.
  
  
  CONCLUSIONS
  Apoptosis after X-ray irradiation develops relatively late in rat SMG. Irradiation reduces AQP5 and TGF-β expression in different SMG cell types.
authors.affiliation: Department of Radiation Oncology, Chung-Ang University Hospital, Seoul, Korea.
authors.forename: Jin Hwa
authors.initials: JH
authors.lastname: Choi
authors.forename: Hong-Gyun
authors.initials: HG
authors.lastname: Wu
authors.forename: Kyeong Cheon
authors.initials: KC
authors.lastname: Jung
authors.forename: Seung Hee
authors.initials: SH
authors.lastname: Lee
authors.forename: Eun Kyung
authors.initials: EK
authors.lastname: Kwon