(-)-anipamil retards atherosclerosis in Watanabe heritable hyperlipidemic rabbits

Calcium antagonists have been reported to limit atherosclerosis in cholesterol fed rabbits. The purpose of this study was to examine the effect of the calcium antagonist (-)-anipamil on the spontaneous development of atherosclerosis in homozygote WHHL rabbits. From the age of 7 weeks, three groups of rabbits received 0 (control, n = 11), 1 mg/kg body weight (n = 11), or 10 mg/kg body weight (n = 12) of (-)-anipamil for 17 weeks. Serum cholesterol at start of the investigation was 18.8 +/- 1.2 (mean +/- SEM), 20.5 +/- 1.8, and 19.5 +/- 0.8 mM, respectively, in the three groups. No significant differences were found in serum lipids (i.e., VLDL, IDL, LDL, HDL) in the study period among the three groups. Plasma anipamil at the end of the study was 0.23 +/- 6, and 202 +/- 19 ng/ml, respectively, in the three treatment groups. The degree of atherosclerosis in the abdominal aorta was significantly lower (p < 0.02) in the 10 mg/kg body weight (-)-anipamil group compared with the two other groups. No significant difference was found in the thoracic aorta. It is concluded that (-)-anipamil retards development of atherosclerosis in the abdominal aorta in WHHL rabbits.