title: Expression and cell-specific localization of cholecystokinin receptors in rat lung.
abstract: OBJECTIVE
  To elucidate whether CCK receptors exist in lung tissues and their precise cellular localization in the lung.
  
  
  METHODS
  CCK-AR and CCK-BR mRNA expression and cellular distribution in the rat lung were detected by highly sensitive method of in situ reverse transcription-polymerase chain reaction (RT-PCR) and conventional in situ hybridization.
  
  
  RESULTS
  CCK-AR and CCK-BR gene positive signals were observed in bronchial epithelial cells, alveolar epithelial cells, pulmonary macrophages and vascular endothelial cells of the rats' lung by in situ RT-PCR. The hybridization signals of CCK-AR were relatively faint. By in situ hybridization, however, only the signals of CCK-BR but not CCK-AR were detected in the lung, and the positive staining was only found in vascular endothelial cells and macrophages.
  
  
  CONCLUSIONS
  CCK-AR and CCK-BR gene were present in pulmonary vascular endothelial cells, macrophages, bronchial epithelial cells and alveolar epithelial cells, which play an important role in mediating the regulatory actions of CCK-8 on these cells.
authors.affiliation: Department of Pathophysiology, Hebei Medical University, Shijiazhuang 050017, Hebei Province, China.
authors.forename: Bin
authors.initials: B
authors.lastname: Cong
authors.forename: Shu-Jin
authors.initials: SJ
authors.lastname: Li
authors.forename: Yi-Ling
authors.initials: YL
authors.lastname: Ling
authors.forename: Yu-Xia
authors.initials: YX
authors.lastname: Yao
authors.forename: Zhen-Yong
authors.initials: ZY
authors.lastname: Gu
authors.forename: Jun-Xia
authors.initials: JX
authors.lastname: Wang
authors.forename: Hong-Yu
authors.initials: HY
authors.lastname: You
mesh_terms: D000818:Animals; D017403:In Situ Hybridization; D008168:Lung / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D043886:Receptor, Cholecystokinin A; D043887:Receptor, Cholecystokinin B; D011949:Receptors, Cholecystokinin / Q000235:genetics / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014018:Tissue Distribution
chemical_list: D012333:RNA, Messenger; D043886:Receptor, Cholecystokinin A; D043887:Receptor, Cholecystokinin B; D011949:Receptors, Cholecystokinin