ABSTRACT
Objective To investigate the urinary endothelin-1 (ET-1) excretion and urinary sodium excretion,microalbuminuria and ambulatory blood pressure(ABP) in salt-sensitive(SS) hypertension patients. Methods Twenty-one cases of normotensive subjects and 32 cases of uncomplicated hypertensive patients were recruited in this study. Salt sensitivity was determined by acute venous saline loading test. Before saline loading, 24-hour ABP measurements were performed. Urine samples were collected to assay ET-1 ,urinary sodium excretion and urinary albumin excretion(UAF). Results Compared to slat-resistant(SR) subgroup, SS showed low urinary ET-1 excretion in normotensive group (P＜0.05) or hypertensive group (P＜0.01) ,regardless of saline loading or not. The nighttime MAP of SS was higher than SR subgroup in normotensive or hypertensive group. Urinary sodium excretion during 4h of saline loading was significantly lower in SS than that in SR hypertensive patients (P＜0. 05). Twenty-four-hour UAE of SS patients was higher than SR group (P＜0.01). Results of further correlation analysis indicated that the urinary ET-1 excretion was positively related to urinary sodium content and negatively to ABP and UAE. Conclusion Urinary ET-1 is low in SS normotensives or hypertension patients,which may play a role in renal sodium retention and renal impairment of SS hypertension patients.