title: Oxidative stress in patients with essential hypertension: a comparison of dippers and non-dippers.
abstract: BACKGROUND
  Oxidative stress seems to play an important role in the pathophysiology of essential hypertension. We aimed to examine serum MDA, NO, 8-OHdG, ADMA, NT, CoQ10 and TAC as biomarkers of oxidative stress in dipper and non-dipper hypertensive patients.
  
  
  METHODS
  Eighteen dipper hypertensives, 20 non-dipper hypertensives and 22 healthy control subjects were included in the study. Clinical assessment and ambulatory blood pressure monitoring were performed in patients. Serum MDA, TAC and NO levels were measured by using spectrophotometric methods. CoQ10 levels were measured by HPLC method. 8-OHdG, ADMA and NT were quantitated by ELISA methods.
  
  
  RESULTS
  MDA levels were significantly higher in dipper and non-dipper groups compared to controls (p<0.05 and p<0.01, respectively). TAC levels were found at low level in patients dipper and non-dipper patients compared to control group (p<0.01). Higher ADMA and NT levels but lower CoQ10 levels were found in non-dipper group compared to healthy controls (p<0.01, p<0.05, and p<0.05, respectively). ADMA levels were found higher in non-dipper group than those of dipper group (p<0.01).
  
  
  CONCLUSIONS
  Increased ADMA, NT levels and decreased CoQ10 levels in non-dipper hypertensive patients might indicate more severe oxidative stres compared with dipper hypertensive patients, which plays an important role in the development of cardiovascular diseases. Increased MDA and reduced TAC levels might be considered as prospective prognostic markers of the development of cardiovascular diseases in dipper and non-dipper hypertensive patients.
authors.affiliation: Department of Biochemistry, Faculty of Pharmacy, Gazi University, Ankara, Turkey. aymelek@gazi.edu.tr
authors.forename: Aymelek
authors.initials: A
authors.lastname: Gönenç
authors.forename: Aysun
authors.initials: A
authors.lastname: Hacışevki
authors.forename: Yusuf
authors.initials: Y
authors.lastname: Tavil
authors.forename: Atiye
authors.initials: A
authors.lastname: Çengel
authors.forename: Meral
authors.initials: M
authors.lastname: Torun
mesh_terms: D000975:Antioxidants / Q000378:metabolism; D001120:Arginine / Q000031:analogs & derivatives / Q000097:blood; D015415:Biomarkers / Q000097:blood*; D001794:Blood Pressure / Q000502:physiology*; D018660:Blood Pressure Monitoring, Ambulatory; D002940:Circadian Rhythm; D005260:Female; D006801:Humans; D006973:Hypertension / Q000097:blood* / Q000503:physiopathology; D008297:Male; D008315:Malondialdehyde / Q000097:blood; D008875:Middle Aged; D018384:Oxidative Stress; D011446:Prospective Studies; D014443:Tyrosine / Q000031:analogs & derivatives / Q000097:blood
chemical_list: D000975:Antioxidants; D015415:Biomarkers; C002744:3-nitrotyrosine; D014443:Tyrosine; D008315:Malondialdehyde; C018524:N,N-dimethylarginine; D001120:Arginine