Expression and cell-specific localization of cholecystokinin receptors in rat lung.
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.
Cong
Bin
B
Department of Pathophysiology, Hebei Medical University, Shijiazhuang 050017, Hebei Province, China.
Li
Shu-Jin
SJ
Ling
Yi-Ling
YL
Yao
Yu-Xia
YX
Gu
Zhen-Yong
ZY
Wang
Jun-Xia
JX
You
Hong-Yu
HY
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
D012333:RNA, Messenger; D043886:Receptor, Cholecystokinin A; D043887:Receptor, Cholecystokinin B; D011949:Receptors, Cholecystokinin