title: [Effects of withdrawal of statins on nitric oxide production in vascular endothelial cells].
abstract: OBJECTIVE
  To investigate the effects of withdrawal of statins on endothelial nitric oxide production in human umbilical vein endothelial cells (HUVECs).
  
  
  METHODS
  HUVECs were treated with simvastatin or lovastatin (10(-6) mmol/L) for 24 hours, then the drugs were replaced by a medium. At 6, 12, 18 and 24 hours after stopping statin treatment, nitric oxide production was measured with Griess reagents. Levels of endothelial nitric oxide synthase (eNOS) mRNA were examined with reverse transcription polymerase chain reaction (RT-PCR).
  
  
  RESULTS
  After 24 hours of incubation, both simvastatin and lovastatin increased the nitric oxide production by (173 +/- 33)% and (170 +/- 44)% respectively and the production of nitric oxide at 24 hours after withdrawal of statins decreased by (64 +/- 9)% and (49 +/- 10)% respectively. These effects of simvastatin and lovastatin on eNOS mRNA expression correlated with changes in nitric oxide production.
  
  
  CONCLUSIONS
  Withdrawal of statins can decrease the production of nitric oxide and the expression of eNOS mRNA, which may account for high cardiovascular events rate in clinical study when statins treatment was stopped abruptly.
authors.affiliation: Department of Cardiology, People's Hospital, Peking University, Beijing 100044, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Xing
authors.forename: Hong
authors.initials: H
authors.lastname: Chen
authors.forename: Da-Yi
authors.initials: DY
authors.lastname: Hu
mesh_terms: D002478:Cells, Cultured; D042783:Endothelial Cells / Q000187:drug effects / Q000378:metabolism*; D004730:Endothelium, Vascular / Q000166:cytology / Q000378:metabolism*; D006801:Humans; D008148:Lovastatin / Q000494:pharmacology*; D009569:Nitric Oxide / Q000096:biosynthesis*; D019001:Nitric Oxide Synthase / Q000235:genetics / Q000378:metabolism*; D052250:Nitric Oxide Synthase Type III; D012333:RNA, Messenger / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D019821:Simvastatin / Q000494:pharmacology*
chemical_list: D012333:RNA, Messenger; D009569:Nitric Oxide; D008148:Lovastatin; D019821:Simvastatin; C496314:NOS3 protein, human; D019001:Nitric Oxide Synthase; D052250:Nitric Oxide Synthase Type III