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Coronary heart disease leads to myocardial infarction and is a major cause of death in the United States. Myocardial infarctions result from atherosclerotic plaque deposits inthecoronary atiefies, ‘educing blood flow through these arteries which supply oxygen and nutrients to the heart muscle. The two major approaches for restoring adequate blood flow are “coronary bypass graft surgery” md “coronary angioplasty”. Angioplasty is a routinely used clinical procedure, where a deflated ~alloon attached to the end of a long catheter is inserted into an artery in the leg and then advanced through the aorta into the blocked regions of the coronary arteries. After positioning in he occluded region of the artery, the balloon is inflated with a pressurized saline solution which >pens the artery restoring blood flow by pressing the atherosclerotic plaque into the vessel wall. Wgioplasty is a widely performed procedure with the coronary arteries and is a much less ?xpensive alternative to coronary bypass surgery. The best patients for angioplasty are those with jingle occlusions and this method is preferred over bypass grafting because of the significantly educed expense. The reformation of plaque deposits in arteries (restenosis) following angioplasty, lowever, is a major clinical problem encountered in as high as 40 percent of patients. Because eduction of health care costs is a major national priority, development of effective new preventative nethods for restenoses is an important national priority. ‘he biological response to such controlled vessel damage after angioplasty is the stimulation of accelerated growth of the smooth muscle cell layer which lines the artery with the resulting build lp of additional plaque, thus leading to resteno”sis. A major current area of vascular biology is the Development of methods to inhibit this restenosis after angioplasty. Although a variety of pharmacological approaches such as the use of corticosteroids, heparin, and other drugs are being