Amlodipine reduces graft coronary artery disease in rat heterotopic cardiac allografts.

The long-acting dihydropyridine calcium antagonist, amlodipine, suppresses atherogenesis in experimental animals. To determine the effect of amlodipine on allograft coronary artery disease in the transplanted heart, we used a working heterotopic rat heart transplant model. All rats were immunosuppressed with cyclosporine as a single agent and randomized to a control group (n = 9) and an amlodipine-treated group (n = 9). After 90 days, rats were killed, and the extent of graft coronary artery disease was assessed by digitizing morphometry. No significant differences were noted for mean arterial blood pressure or serum total cholesterol, high-density lipoprotein cholesterol, or triglycerides at the time of death. Amlodipine was associated with significantly less narrowing in the coronary arteries (mean percent narrowing for control group, 48.9% +/- 8.2%; mean percent narrowing for amlodipine group, 25.5% +/- 9.9%; P < 0.05). These findings suggest a role for calcium channel blockers in the prevention of graft coronary artery disease.