eNOS genotype is without effect on circulating nitrite/nitrate level in healthy male population.
BACKGROUND
Nitric oxide (NO) plays an important role in the regulation of the cardiovascular system. It is produced by endothelial nitric oxide synthase (eNOS), which exhibits genetic polymorphisms. Although the clinically relevant polymorphism T(+IhI-786)C reduces eNOS-promoter activity, it is not clear whether circulating nitrite/nitrate (NOx) are affected by this polymorphism.


METHODS
We addressed this issue by studying a homogeneous group of 200 healthy subjects (males, Caucasians, nonsmokers, 18+IBM-56 years of age, and not taking any medication). Genotypes were determined by restriction fragment length polymorphism and circulating NOx were determined by chemiluminescence.


RESULTS
We found nonsignificant effects of the T(+IhI-786)C polymorphism on circulating NOx (mean+ALE-S.D.=52.2+ALE-21.4, 49.0+ALE-17.8, and 45.9+ALE-16.8 +A7w-mol/L for genotypes +IBw-TT,+IB0 +IBw-TC,+IB0 and +IBw-CC,+IB0 respectively) and on total plasma cholesterol concentrations (both P>.05). No correlation was found between circulating NOx and total plasma cholesterol concentrations (P>.05).


CONCLUSIONS
Our study provides strong evidence that the T(+IhI-786)C polymorphism does not affect plasma NOx concentrations, which are believed to reflect endogenous production of NO. Therefore, our results suggest that this polymorphism does not affect endogenous NO production.
Nagassaki
Sabrina
S
Department of Pharmacology, Faculty of Medicine of Ribeirao Preto, University of Sao Paulo, Av. Bandeirantes, 3900, 14049-900 Ribeirao Preto, SP, Brazil.
Metzger
Ingrid F
IF
Souza-Costa
Debora C
DC
Marroni
Aline S
AS
Uzuelli
Juliana A
JA
Tanus-Santos
Jose E
JE
D000293:Adolescent; D000328:Adult; D001938:Brazil; D005838:Genotype; D006801:Humans; D008163:Luminescent Measurements; D008297:Male; D008875:Middle Aged; D009566:Nitrates / Q000097:blood*; D009569:Nitric Oxide / Q000096:biosynthesis / Q000378:metabolism; D019001:Nitric Oxide Synthase / Q000235:genetics* / Q000378:metabolism; D052250:Nitric Oxide Synthase Type III; D009573:Nitrites / Q000097:blood*; D011110:Polymorphism, Genetic / Q000235:genetics; D011153:Population / Q000235:genetics*; D012016:Reference Values; D012737:Sex Factors; D044465:White People / Q000235:genetics*
D009566:Nitrates; D009573:Nitrites; D009569:Nitric Oxide; C496314:NOS3 protein, human; D019001:Nitric Oxide Synthase; D052250:Nitric Oxide Synthase Type III