Abstract: Objective To investigate the relationship of the T786C polymorphism of endothelial nitric oxide synthase(eNOS) gene to essential hypertension(EH) in Chinese population.Methods Polymerase chain reaction combined with restriction enzyme digestion was used to detect the polymorphism of eNOS gene in 167 normotensive subjects controls and 267 hypertensive patients;Fasting serum nitric oxide metabolite(NOx) and Endothelin(ET) were measured by nitrate reductase and radioimmunoassay respectively.Results 1) The frequencies of C allele and CC+CT genotype in EH were significantly higher than those in control group(P<0.01);2) The level of NOx and the rate of NOx/ET were higher in TT genotype [(77.68±33.36)μmol/L,1.41±1.28] than those in CT+CC genotype [(67.15±24.22)μmol/L,0.93±0.51] of EH.The level of ET were lower in TT genotype [(68.70±29.04)ng/L] than in CT+CC genotype [(78.23±31.17)ng/L] of EH.Conclusion It is suggested that the T786C pollymorphism of eNOS gene is reltated to EH in Chinese population.C allele may be involved in the etiology of EH by reducing NO release of endothelium.

Key words: essential hypertension, nitric oxide synthase, polymorphism, nitric oxide