THE ANTIATHEROGENIC EFFECT OF NIFEDIPINE ON INTRAMURAL SMALL CORONARYARTERIAL LESIONS IN CHOLESTEROL-FED RABBITS

The objective of this study was to examine the suppressive effect of n ifedipine on intramural coronary arterial lesions in cholesterol-fed r abbits. Each rabbit in Groups A (n=6) and B (n=5) was fed a 0.3% chole sterol diet and was orally administered nifedipine (40 mg/day) or plac ebo. Each rabbit in Groups C (n=5) and D (n=6) was fed a 0.5% choleste rol diet and was orally administered nifedipine (40 mg/day) or placebo . The serum concentrations of total cholesterol (TC) were determined a t 1-week intervals to calculate the integrated values. The lesion indu ction ratio was defined as the ratio of intramural coronary arteries 5 0-150 mu m in diameter with arterial lipoidosis to the total number of arteries of the same diameter. There were no significant differences between the nifedipine-treated and placebo groups in either the integr ated TC or lesion induction ratio in either the 0.3% and 0.5% choleste rol-fed rabbits. This study demonstrates that nifedipine does not supp ress atherogenesis in the intramural small coronary arteries of choles terol-fed rabbits.