title: [Effect of hypoxia on expression of iNOS mRNA in cultured rat astrocytes].
abstract: OBJECTIVE
  To explore the effects of hypoxia on expression of inducible nitric oxide synthase (iNOS) mRNA in cultured rat astrocytes.
  
  
  METHODS
  Cultured rat astrocytes were randomly divided into 4 groups: glutamate group (G), hypoxic group (H), hypoxia + glutamate group (H + G) and the control (C). Cells of control group were exposed to normoxic (95% air, 5% CO2) condition, and cells of G and H + G were incubated with 100 micromol/L L-glutamate, cells of H and H + G exposed to hypoxic conditions (5% CO2, 95% N2) at 37 degrees C. Each group had five timepoints which included 0 h, 3 h, 6 h, 12 h, 24 h, respectively. Expression of mRNAs of iNOS were detected with reverse transcription polymerase chain reaction (RT-PCR).
  
  
  RESULTS
  Expression of iNOS mRNA was not detectable in G and C, while it increased dramatically and continuously from 6 h to 24 h in H and G + H. Expression of iNOS mRNA was significantly higher in H than both in G and C at 6 h, 12 h and 24 h, and expression of iNOS mRNA was the highest of all groups in G + H.
  
  
  CONCLUSIONS
  Hypoxia upregulates the expression of iNOS mRNA in cultured astrocytes. Glutamate does not induce the expression of iNOS mRNA but enhance the effect of hypoxia, which is maybe one of the adaptive mechanisms of hypoxia-induced cerebral dilation.
authors.affiliation: Department of Pathophysiology, College of High Altitude Military Medicine, Third Military Medical University, Chongqing 400038, China.
authors.forename: You-Ming
authors.initials: YM
authors.lastname: Fan
authors.forename: Yu-Qi
authors.initials: YQ
authors.lastname: Gao
authors.forename: Guo-Bin
authors.initials: GB
authors.lastname: Zhang
authors.forename: Wen-Xiang
authors.initials: WX
authors.lastname: Gao
authors.forename: Shu-Min
authors.initials: SM
authors.lastname: Xu
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D001253:Astrocytes / Q000187:drug effects / Q000378:metabolism*; D015687:Cell Hypoxia; D002478:Cells, Cultured; D002540:Cerebral Cortex / Q000166:cytology; D018698:Glutamic Acid / Q000494:pharmacology; D009569:Nitric Oxide / Q000096:biosynthesis; D052247:Nitric Oxide Synthase Type II / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics; D051381:Rats
chemical_list: D012333:RNA, Messenger; D009569:Nitric Oxide; D018698:Glutamic Acid; D052247:Nitric Oxide Synthase Type II; C496318:Nos2 protein, rat