title: Relation of endothelial nitric oxide synthase gene to plasma nitric oxide level, endothelial function, and blood pressure in African Americans.
abstract: BACKGROUND
  The role of eNOS gene polymorphisms on plasma nitrite or nitrate (NOx) level, endothelial function, and blood pressure (BP) remains unclear.
  
  
  METHODS
  We estimated the relationship of eNOS polymorphisms (the T(-786)C in the 5'-flanking promoter region, T(-786)C; 27-bp repeat in intron 4, eNOS4; and Glu298Asp in exon 7, G894T) with plasma NOx level, brachial endothelial function assessed by ultrasound measure of brachial artery flow-mediated dilation (FMD), and BP in 60 healthy African Americans, 30 men and 30 women aged 18 to 73 years.
  
  
  RESULTS
  Among them, 73.1%, 23.9%, and 3.0% carried TT, TC, and CC of T(-786)C, respectively, 14.5%, 27.5%, 53.6%, and 1.4% carried aa, ab, bb, and bc of eNOS4 polymorphism, respectively, and 70.4%, 23.9%, and 5.6% carried GG, GT, and TT of G894T, respectively. G894T and eNOS4 were observed in linkage disequilibrium. Mean values of age, plasma NOx, FMD, systolic and diastolic BPs were not significantly different (P >.05) by eNOS polymorphisms. Plasma NO(x) level was found to be associated with systolic BP (r = 0.51, P =.03), and diastolic BP (r = 0.41, P =.08), but not with FMD, in individuals with "a" allele of eNOS4 polymorphism after adjustment for age, body mass index, serum glucose, and smoking status.
  
  
  CONCLUSIONS
  We reveal a positive association between plasma NOx level and BP in normotensive African Americans who carry the "a" allele of eNOS4. Because the frequency of the rare allele "a" is significantly higher in African Americans than in other ethnic groups, this finding may provide a clue to understanding the genetic susceptibility to hypertension in African Americans.
authors.affiliation: Department of Medicine, Clinical Research Center, Atlanta, Georgia, USA. rli2@utmem.edu
authors.forename: Rongling
authors.initials: R
authors.lastname: Li
authors.forename: Deborah
authors.initials: D
authors.lastname: Lyn
authors.forename: Rigobert
authors.initials: R
authors.lastname: Lapu-Bula
authors.forename: Adefisayo
authors.initials: A
authors.lastname: Oduwole
authors.forename: Priscilla
authors.initials: P
authors.lastname: Igho-Pemu
authors.forename: Brenda
authors.initials: B
authors.lastname: Lankford
authors.forename: Jan
authors.initials: J
authors.lastname: Morgan
authors.forename: Sunday
authors.initials: S
authors.lastname: Nkemdechi
authors.forename: Gang
authors.initials: G
authors.lastname: Liu
authors.forename: Cheryl
authors.initials: C
authors.lastname: Pack
authors.forename: Natalia
authors.initials: N
authors.lastname: Silvestrov
authors.forename: Daniel A
authors.initials: DA
authors.lastname: von Deutsch
authors.forename: Qing
authors.initials: Q
authors.lastname: Song
authors.forename: Imad K
authors.initials: IK
authors.lastname: Abukhalaf
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Ofili
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000097:blood; D044383:Black People; D001783:Blood Flow Velocity / Q000502:physiology; D001794:Blood Pressure / Q000502:physiology*; D002318:Cardiovascular Diseases / Q000235:genetics / Q000378:metabolism / Q000503:physiopathology; D003971:Diastole / Q000502:physiology; D004730:Endothelium, Vascular / Q000378:metabolism / Q000502:physiology*; D005260:Female; D005787:Gene Frequency / Q000235:genetics; D020022:Genetic Predisposition to Disease / Q000453:epidemiology / Q000235:genetics; D005838:Genotype; D005845:Georgia / Q000453:epidemiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009569:Nitric Oxide / Q000378:metabolism*; D019001:Nitric Oxide Synthase / Q000235:genetics*; D052250:Nitric Oxide Synthase Type III; D011110:Polymorphism, Genetic / Q000235:genetics; D012307:Risk Factors; D013223:Statistics as Topic; D013599:Systole / Q000502:physiology; D014664:Vasodilation / Q000502:physiology; D001741:Black or African American
chemical_list: D015415:Biomarkers; D009569:Nitric Oxide; C496314:NOS3 protein, human; D019001:Nitric Oxide Synthase; D052250:Nitric Oxide Synthase Type III