title: [Effects of hypoxia on proliferation of pulmonary arterial smooth muscle cells].
abstract: OBJECTIVE
  To investigate the effects of hypoxia on the proliferation of different diameter intra-pulmonary artery smooth muscle cells (PASMCs), and to study the possible signal transduction pathway in proliferation caused by hypoxia.
  
  
  METHODS
  PASMCs were isolated from three different size of pulmonary arteries (>1 000 microm, 500-800 microm, 300-400 microm diameter) and cultured separately. 3H-TdR incorporation and cell number were used to measure cell proliferation.
  
  
  RESULTS
  3H-TdR incorporation and cell number of PASMCs from three sizes of pulmonary artery (> 1 000 microm, 500-800 microm, 800-400 microm diameter) increased 23.5% and 11.1%, 60.0% and 33.8%, 141.4% and 52.0%, respectively. Calcium antagonist (verapamil), PKC inhibitor (staurosporine), and Na(+)-H+ exchange inhibitor (amiloride) were used in PASMCs isolated from 300-400 microm diameter pulmonary artery. The results showed that verapamil, staurosporine and amiloride could notably block hypoxia-induced increase 3H-TdR incorporation and cell number.
  
  
  CONCLUSIONS
  Proliferation of pulmonary artery smooth muscle cell responded to hypoxia differently according to the artery size; activation of calcium channel, PKC and Na(+)-H+ exchange might mediate the proliferation initiated by hypoxia.
authors.affiliation: Laboratory of Cardiovascular Physiology, Hunan Medical University, Changsha 410078.
authors.forename: T Z
authors.initials: TZ
authors.lastname: Yu
authors.forename: C T
authors.initials: CT
authors.lastname: Ma
mesh_terms: D000818:Animals; D002455:Cell Division; D015687:Cell Hypoxia; D049109:Cell Proliferation; D002478:Cells, Cultured; D005260:Female; D008297:Male; D009131:Muscle, Smooth, Vascular / Q000166:cytology*; D032389:Myocytes, Smooth Muscle / Q000166:cytology* / Q000378:metabolism; D011651:Pulmonary Artery / Q000166:cytology; D011817:Rabbits; D015398:Signal Transduction