Effect of losartan on plasma endothelins and nitrogen mon oxide in elderly patients with moderate to severe essential hypertension

Objective: To investigate the effect of losartan on plasma endothelins (ET) and nitrogen mon oxide (NO) in elderly patients with moderate to severe essential hypertension. Methods: Forty-eight patients with essential hypertension who were≥60 years of age and had been treated with two or more antihy-pertensive drugs but whose systolic pressure were still≥160mmHg and or whose diastolic pressure were ≥ 100mmHg, entered into the present study. Losartan 50mg daily was added to their original treatment for 6 weeks. ET and NO were measured before and 6 weeks after treatment. Fifty-two healthy adults acted as controls. Results; In the treatment group,ET was significantly decreased and NO was significantly increased after 6 weeks' addition of losartan. As compared with controls, ET of treatment group was higher both before and after addition of losartan (P0.001), NO was lower before addition of losartan (P =0.038) and higher after addition (P = 0.005). Before addition of losartan, the ratio of ET/NO in treatment group (2.2) was higher than that after addition(1.0,P0.0001). After addition of losartan, the ratio of ET/NO in treatment group (1.0) did not differ significantly from that of controls (1.0 P = 0.819). Conclusions;Losartan may improve the endothelial function of elderly patients with moderate to severe essential hypertension.