Abstract: To investigate the effects of bisoprolol on renin-angiotensin-aldosterone syst em(RAAS), endothelial function and its antihypertensive efficacy, the changes of plasma endothelin (ET), nitrogen monoxide(NO), renin(Ren), angiotensin Ⅱ(AngⅡ), aldosterone(Ald) and clinical blood pressure(CBP) were observed before and a fter bisoprolol was taken for 4 weeks in 36 patients with essential hypertension . After 4 weeks treatment of bisoprolol, clinical systolic b lood pressure and clinical diastolic blood pressure decreased to 2.16 kPa(16.23 mmHg) a nd 1.02 kPa(7.65 mmHg) respectively(P< 0.01); Ren, AngⅡ, Ald decreas ed and NO significantly increased(P<0.05 and 0.01 respectively), but NO/ET and ET h ad no any changes(P>0.05). It is suggested that Bisoprolol can not only dec rease blood pressure, but also inhabit RAAS,improve vascular endothelial functi on and protect target organ simultaneously.

Key words: essential hypertension, bisoprolol, renin-angiotensin system, vascular endothelial function