The most commonly performed procedure for treating
coronary artery stenosis is percutaneous transluminal
coronary angioplasty (PTCA) and, where the vessel lumen is
severely narrowed, coronary artery bypass grafting (CABG).
In PTCA, regions of atherosclerotic plaques are disrupted,
and the vessel lumen increased by inflating a balloon
catheter. In CABG an autologous saphenous vein into
coronary artery interposition graft is performed in order to
bypass occluded regions of epicardial coronary arteries.
Both interventions cause varying degrees of vascular damage
and the long-term efficacy of these procedures is limited by
a high incidence of neointimal formation and subsequent
vascular restenosis (Bach et al. 1994; Bryan & Angelini, 1994).
The endothelium-derived constrictor peptide, endothelin-1 (ET-1)
(Yanagisawa et al. 1988), also possesses mitogenic
activity on vascular smooth muscle cells (Hirata et al. 1989)
and has been suggested as playing a role in atherosclerosis
(Dashwood et al. 1993; Zeiher et al. 1994) and intimal
hyperplasia (Dashwood et al. 1993; Douglas et al. 1994).