title: The functional expression of extracellular calcium-sensing receptor in rat pulmonary artery smooth muscle cells.
abstract: BACKGROUND
  The extracellular calcium-sensing receptor (CaSR) belongs to family C of the G protein coupled receptors. Whether the CaSR is expressed in the pulmonary artery (PA) is unknown.
  
  
  METHODS
  The expression and distribution of CaSR were detected by RT-PCR, Western blotting and immunofluorescence. PA tension was detected by the pulmonary arterial ring technique, and the intracellular calcium concentration ([Ca2+]i) was detected by a laser-scanning confocal microscope.
  
  
  RESULTS
  The expressions of CaSR mRNA and protein were found in both rat pulmonary artery smooth muscle cells (PASMCs) and PAs. Increased levels of [Ca2+]o (extracellular calcium concentration) or Gd3+ (an agonist of CaSR) induced an increase of [Ca2+]i and PAs constriction in a concentration-dependent manner. In addition, the above-mentioned effects of Ca2+ and Gd3+ were inhibited by U73122 (specific inhibitor of PLC), 2-APB (specific antagonist of IP3 receptor), and thapsigargin (blocker of sarcoplasmic reticulum calcium ATPase).
  
  
  CONCLUSIONS
  CaSR is expressed in rat PASMCs, and is involved in regulation of PA tension by increasing [Ca2+]i through G-PLC-IP3 pathway.
authors.affiliation: Department of Pathophysiology, Qiqihar Medical University, Qiqihar 161006, PR China.
authors.forename: Guang-wei
authors.initials: GW
authors.lastname: Li
authors.forename: Qiu-shi
authors.initials: QS
authors.lastname: Wang
authors.forename: Jing-hui
authors.initials: JH
authors.lastname: Hao
authors.forename: Wen-jing
authors.initials: WJ
authors.lastname: Xing
authors.forename: Jin
authors.initials: J
authors.lastname: Guo
authors.forename: Hong-zhu
authors.initials: HZ
authors.lastname: Li
authors.forename: Shu-zhi
authors.initials: SZ
authors.lastname: Bai
authors.forename: Hong-xia
authors.initials: HX
authors.lastname: Li
authors.forename: Wei-hua
authors.initials: WH
authors.lastname: Zhang
authors.forename: Bao-feng
authors.initials: BF
authors.lastname: Yang
authors.forename: Guang-dong
authors.initials: GD
authors.lastname: Yang
authors.forename: Ling-yun
authors.initials: LY
authors.lastname: Wu
authors.forename: Rui
authors.initials: R
authors.lastname: Wang
authors.forename: Chang-qing
authors.initials: CQ
authors.lastname: Xu
mesh_terms: D000818:Animals; D001483:Base Sequence; D015153:Blotting, Western; D001896:Boron Compounds / Q000494:pharmacology; D002118:Calcium / Q000494:pharmacology; D002121:Calcium Channel Blockers / Q000494:pharmacology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D004963:Estrenes / Q000494:pharmacology; D005455:Fluorescent Antibody Technique; D066298:In Vitro Techniques; D008297:Male; D008969:Molecular Sequence Data; D032389:Myocytes, Smooth Muscle / Q000166:cytology / Q000378:metabolism; D011651:Pulmonary Artery / Q000166:cytology / Q000378:metabolism*; D011760:Pyrrolidinones / Q000494:pharmacology; D012333:RNA, Messenger / Q000235:genetics; D051381:Rats; D017208:Rats, Wistar; D044169:Receptors, Calcium-Sensing / Q000235:genetics* / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D019284:Thapsigargin / Q000494:pharmacology; D010738:Type C Phospholipases / Q000037:antagonists & inhibitors
chemical_list: D001896:Boron Compounds; D002121:Calcium Channel Blockers; D004791:Enzyme Inhibitors; D004963:Estrenes; D011760:Pyrrolidinones; D012333:RNA, Messenger; D044169:Receptors, Calcium-Sensing; C060229:1-(6-((3-methoxyestra-1,3,5(10)-trien-17-yl)amino)hexyl)-1H-pyrrole-2,5-dione; D019284:Thapsigargin; C109986:2-aminoethoxydiphenyl borate; D010738:Type C Phospholipases; D002118:Calcium