A Potential Role for Endothelin-1 in Peripheral Vascular Disease

The distribution of endothelin-1 (ET-1) and its receptors (ETA/ETB) has been studied in segments of femoral artery obtained from patients undergoing operation for peripheral vascular disease (PVD) using a combination of immunohistochemistry and autoradiography. Both receptor subtypes were located on the tunica media of vessel segments, with ETA-receptors predominating. Densitometric analysis showed that there was no difference in receptor binding to proximal/distal arterial segments from PVD patients. High-resolution autoradiography identified ETB binding to vascular nerves and vasa vasorum, mainly in distal portions of femoral arteries. Immunoreactive ET-1 was also identified that was associated with the vasa vasorum.