title: [Amiloride attenuates hypoxia-induced proliferation of rats pulmonary artery smooth muscle cells by suppressing Na+/ H+ exchanger-1].
abstract: OBJECTIVE
  To study the influence of Na+/H+ exchange inhibitor amiloride on hypoxia-induced proliferation in rats pulmonary artery smooth muscle cells (PASMCs), also observe the change of Na+/H+ exchanger-1 (NHE-1) activity and expression.
  
  
  METHODS
  Rats PASMGs were cultured in normoxia (21% O2) or hypoxia (2%O2) for 24 hours, as well as administered amiloride with various concentrations, cultured for 24 hours, then determined MTT OD values and rates of PCNA positive cells to investigate cells proliferation, moreover intracellular pH was determined by interactive Laser Cytometer, and Na+/H+ exchanger-1 mRNA expression was determined by RT-PCR.
  
  
  RESULTS
  Hypoxic exposure heightened intracellular pH and mRNA expression of NHE-1 in PASMCs, however, 3.123-50 micromol/L amiloride depressed them gradually. Additionally, hypoxic exposure raised MTT OD value and rates of PCNA positive cells, similarly, the above two indexes descended gradually with presence of 3.125-50 micromol/L amiloride.
  
  
  CONCLUSIONS
  Na+/H+ exchange inhibitor amiloride can suppress hypoxia-induced proliferation in pulmonary artery smooth muscle cells, which is due to depress activity and expression of NHE-1.
authors.affiliation: Department of Pathophysiologvy, Fourth Military Medical University, Xi'an 710032, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Liu
authors.forename: Ming-qing
authors.initials: MQ
authors.lastname: Dong
authors.forename: Wen
authors.initials: W
authors.lastname: Niu
authors.forename: Bo
authors.initials: B
authors.lastname: Zhang
authors.forename: Ying
authors.initials: Y
authors.lastname: Luo
authors.forename: Zhi-chao
authors.initials: ZC
authors.lastname: Li
mesh_terms: D000584:Amiloride / Q000494:pharmacology*; D000818:Animals; D015687:Cell Hypoxia; D049109:Cell Proliferation / Q000187:drug effects*; D008297:Male; D009131:Muscle, Smooth, Vascular / Q000166:cytology; D032389:Myocytes, Smooth Muscle / Q000166:cytology / Q000187:drug effects*; D011651:Pulmonary Artery / Q000166:cytology / Q000187:drug effects; D051381:Rats; D017207:Rats, Sprague-Dawley; D026941:Sodium Channel Blockers / Q000494:pharmacology*; D017923:Sodium-Hydrogen Exchangers / Q000037:antagonists & inhibitors / Q000378:metabolism*
chemical_list: D026941:Sodium Channel Blockers; D017923:Sodium-Hydrogen Exchangers; D000584:Amiloride