Exaggerated Endothelin Release in Response to Acute Mental Stress in Patients with Intermittent Claudication

Endothelin-1 (ET-1) is an endothelial-derived 21-amino-acid peptide with potent vasocon strictor and mitogenic properties implicated in several cardiovascular disorders. To evaluate the plasma ET-1 response to mental stress in patients with intermittent claudication, plasma endothelin concentrations were measured by radioimmunoassay in 15 claudicant outpatients (13 men and 2 women; mean age 62 ±4 years) and in 15 sex- and age-matched healthy control subjects (12 men and 3 women; mean age 60 ±8 years) before and after mental arithmetic performed for 10 minutes. Venous blood samples were drawn from an antecubital vein at baseline, at the end of the mental arithmetic, and at 10 minutes of recovery. Baseline ET-1 values were higher in patients with intermittent claudication as compared with control subjects (4.5 ±0.5 pmol/L and 2.2 ±0.3 pmol/L, respectively, p