The A1166C polymorphism of the Angiotensin II type I receptor gene and the response to antihypertensive agents in the elderly
Chunping Zhang · Chinese Journal of Hypertension · 2002
Objective To investigate the distribution of A1166C polymorphism of the type Ⅰ angiotensin Ⅱ receptor (AT 1-R) gene in elderly hypertensive population and impact of polymorphism on the responese of BP after treatment with losartan and ACEI. Methods One hundred eighty six hypertensive subjects were randomly recruited from geriatric department in Shanghai. A→C polymorphic site at 1166 nucleotide position in the 3'-untranslated region of AT 1-R is determined using restriction length polymorphism analysis of DNA generated by polymerase chain reaction(PCR-RFLP). Sixty hypertensive subjects with average age of 71±6 yrs are divided into 2 groups according to genotypes and randomized to either an losartan or ACEI. Fifty-seven patients (AA=41,AC=16) were follow-up for 24 wks. Results (1)The frequency of C allele is 0.062. (2)Losartan decreased 24 hr,daytime,nighttime SBP by 7.4%,7.6%,and 6.8% and DBP by 6.5%,6.4%,7.4%,respectively in AA homoxygotes. ACEI decreased 24 h,daytime SBP by 6.2%,7.1% in AA homoxygotes. In AC hetrozygotes, after losartan treatment,the 24 hr SBP, daytime SBP, DBP were reduced by 5.2%, 5.6%, 5.6% in AC hetrozygotes. After ACEI treatment, the 24 hr SBP daytime SBP were reduced by 5.0%,5.8% in AC hetrozygotes. 2×2 fractorial analysis showed no interaction between genotypes and the effect of treatment. Conclusion A low allele frequency of A1166C was found in elderly Shanghai hypertensive. Although losartan and ACEI reduced SBP and DBP,no difference in response rate has been found in homozygotes and hetrozygotes. It seems the effect of losartan and ACEI on hypertension was independent from the genotypes of the patients with hypertension.