Objective: To investigate the association between M235T variant of angiotensinogen (AGT) gene and the blood pressure response to benazepril in a hypertensive cohort.
Methods: Benazepril (10-20 mg/day) was administered for 6 weeks to 251 essential hypertensives. Polymerase chain reaction (PCR) combined with restriction enzyme digestion was used to detect the polymorphism and the patients were classified as MM, MT or TT genotype. The changes in systolic and diastolic blood pressure (SBP and DBP) were analyzed for association with genotypes at the AGT gene locus.
Results: The MM genotype was observed in 23 patients (9.2%), the MT genotype in 104 patients (41.4%) and the TT genotype in 124 patients (49.4%). There was no association between these polymorphisms and the blood pressure responses in the total 251 patients. But based on the analysis stratified by age, the association between these polymorphism and the DBP responses was found in the old patients (> or = 60 years old) subgroup, the reduction in DBP was significantly greater in patients carrying the MM compared to MT or TT genotypes (14.8 +/- 4.8 mm Hg vs. 7.9 +/- 7.7 mm Hg or 9.8 +/- 6.4 mm Hg respectively; ANOVA, P = 0.034).
Conclusion: The M235T polymorphism of the AGT gene was shown to influence the responses to benazepril in old hypertensive patients (> or = 60 years old). Thus, specific genotypes might predict the response to specific antihypertensive treatment.