RESUMO
Objective The purpose of this study was to investigate the association of AGTR1 promoter methylation with the risk of essential hypertension (EH),and to explore whether the methylation levels of AGTR1 were influenced by antihypertensive drug therapy.Methods In the current case-control study,with community population-based multi-stage sampling method,a total of 288 individuals including 96 controls,96 gender-and age-matched incidence essential hypertension(In-EH) patients and 96 gender-and age-matched prevalent essential hypertension(Pre-EH) patients were recruited from Han Chinese families in Ningbo City.The baseline data,blood samples and serum biochemical indexes of participants were obtained through questionnaire,conventional check-up and laboratory detection.Methylation levels of CpGdinucleotides in genepromoter of AGTR1 were measured using bisulfite pyrosequencing.Conditional logistic regression was used to adjust for confounding factors,and find the CpG sites which were sensitive to EH and drug.Results Body mass index,triglycerides,fasting blood glucose,high-density lipoprotein and uric acid among the three groups were significantly different (P ＜ 0.05).Conditional logistic regression showed that methylation of CpG1 was significantly lower in both In-EH and Pre-EH than in controls (Controls vs.In-EH):9.66 ± 5.45 vs.6.74 ± 4.32,OR =0.888,95 ％ CI:0.792-0.995;(Controls vs.Pre-EH):9.66 ± 5.45 vs.4.99 ± 3.97,OR =0.454,95 ％ CI:0.226-0.913.No significant result was observed between In-EH and Pre-EH (P ＞ 0.05).Conclusion Hypomethylation of CpG1 in AGTR1 gene is a risk factor for EH.However,no effect of antihyptensive drug therapy on the changes of DNA methylation levels in AGTR1 was found.