Abstract: AIM: To investigate the relationship between the therapeutic effect of enalapril on blood pressure reduction and ACE genetic polymorphisms. METHODS: The genotypes of ACE in 68 patients with essential hypertension were determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP)assay.All subjects were randomly divided into three groups (group DD, group Ⅱ, and group ID)according to their different ACE genotypes.68 patients with essential hypertension were treated with 20 mg enalapril daily for 2 consecutive weeks.The changes of systolic and diastolic blood pressure in all subjects were observed before and after enalapril administration.RESULTS: The data showed that there were significantly statistical difference in the systolic blood pressure and diastolic blood pressure in three groups' patients with essential hypertension between before and after enalapril administration (P<0.05).Additionally, there was marked difference in the differential values of systolic blood pressure and diastolic blood pressure reduction between group DD and group Ⅱ(P<0.05).The total efficacy rate of enalapril treatment was 91.30 % in group DD, 85.71 % in group ID, and 79.16 % in groupⅡrespectively, which indicated enalapril had the best effect on blood pressure reduction in DD genotyped group.CONCLUSION: The therapeutic effect of enalapril on blood pressure reduction is associated with ACE genetic polymorphism and the essential hypertensive patients with DD genotypes had the best response to enalapril treatment compared with ID genotypes andⅡgenotypes.

Key words: essential hypertension, gene polymorphism, ACE, enalapril