Objective. To assess the relationship between the serum level of endothelin-1, renal function, and the presence and severity of endothelial dysfunction.
Material and methods. 80 CKD patients aged 26 to 79 (58.9±1.4) years were selected for this study: 43 women (average age 60.1±1.9 years) and 37 men (average age 57.4±2.3 years). The cohort of patients was divided into 2 groups: group 1 consisted of 40 patients (28 women and 12 men) with CKD 3A-5 (average age 59.9±2.1 years), group 2 - 40 patients (18 women and 22 men) with CKD 5D (average age 58.1±2.1 years). In all patients, clinical and anamnestic data were assessed, laboratory studies were carried out, the serum level of endothelin-1 was determined, bioimpedance analysis was performed, a test with endothelium-dependent vasodilation was performed using ultrasound examination of the brachial artery. Statistical analysis was performed using Statistica 10.0 software.
Results. The level of endothelin-1 was higher in the group of patients receiving treatment with programmed hemodialysis: 54.1±0.7 pg/ml versus 45.7±1.4 pg/ml, respectively. The prevalence of endothelial dysfunction in the general cohort of patients according to the test data was 48.8% of cases (in the 1st group – 27.5%, and in the 2nd group – 70%; p=0.001). A strong negative correlation was found between endothelin-1 and GFR. Moderate correlation of endothelin-1 was found with urea, abnormalities in total fluid volume, extracellular fluid volume, duration of CKD, sodium and total serum protein levels. Endothelin-1 values were higher than the median in 17.5% in group 1 and 55% in group 2. In the 2nd group, there was more often a concomitant increase in the level of endothelin-1 and a positive test with endothelial vasodilation than in the 1st group, 30% versus 2.5%.
Conclusion. Our study allowed us to assess the prevalence and severity of endothelial dysfunction in patients with CKD at different stages. The endothelium-dependent vasodilation test can be used as an additional assessment method. Endothelin-1 has shown a high predictive potential for endothelial dysfunction.

Keywords: vascular remodeling, endothelial dysfunction, endothelin-1, chronic kidney disease