Abstract: AIM: To explore effect of renin-angiotension-aldosterone system induced by bisoprolol with different time drug administration in patients with non-dipper hypertension.METHODS: The patients were randomly divided into two parallel groups. All patients were treated with bisoprolol. The first group were received bisoprolol at eight o'clock once-daily between 2.5 mg and 10 mg. The second group were received bisoprolol at twenty o'clock once-daily between 2.5 mg and 10 mg. The concentration of rennin,angiotension and aldosterone after 8 weeks' treatment were detected and evaluated.RESULTS: The concentration of rennin,angiotension and aldosterone after treatment were lower than before treatment in two groups(P<0.05). And there was no significant difference between two groups on the concentration of renin (P>0.05), but a significant difference on angiotension and aldosterone(P<0.05).CONCLUSION: Two methods of treatment can decrease the concentration of rennin,angiotension and aldosterone, but the non-dippers hypertension taked drug at eight o'clock has a signifcant effect on angiotension and aldosterone.

Key words: Bisoprolol, Non-dippers hypertension, Renin-angiotension-aldosterone system  ,  ,  ,  ,