101 patients (71 persons with silicosis of foundry workers in combination with arterial hypertension (АH), 30 patients with silicosis) aged 54.9±4.87 years, with working experience of 22.7±5.41 years were examined. Endothelial dysfunction was manifested by elevation of ЕТ-1 and was more expressed in patients with combined pathology. Changes of ЕТ-1 and FN was accompanied by ventilation disturbances and, as markers of endothelial dysfunction and inflammatory processes, may be associated with hypoxia and metabolic changes.