Abstract
The effects of diltiazem on the suppression and regression of atherosclerosis were studied. Thirty-one rabbits were fed a 1% cholesterol (atherogenic) diet with the injection of saline (n=22) or diltiazem (n=9). After 10 weeks of feeding, 7 rabbits on the atherogenic diet with saline (n=7) or diltiazem (n=9) were killed. The remaining fifteen rabbits fed the atherogenic diet with saline were put on a standard (regression) diet with the injection of saline (n=7) or diltiazem (n=8) for the next 15 weeks.
As a control, 16 rabbits on a standard diet were used, half of which were killed at 10 weeks and other half were fed for the next 15 weeks.
The plasma LDL cholesterol level in the rabbits on the atherogenic diet with diltiazem was significantly lower than in those on the atherogenic diet with saline at 5 and 10 weeks. The aortic total cholesterol, esterified cholesterol, and calcium in rabbits on the atherogenic diet with diltiazem were significantly lower than in the rabbits on the atherogenic diet with saline.
At the end of 25 weeks (15 weeks on regression diet), plasma concentration of total, VLDL, LDL and HDL cholesterol, and triglyceride showed no differences in three groups.
Differences in aortic total cholesterol and calcium between two groups of regression diet were also insignificant, but aortic esterified cholesterol in the group of regression diet with diltiazem was significantly lower than in the group of regression diet with saline and in the group of atherogenic diet with saline.
The results suggested that diltiazem had a favorable effects on regression as well as suppression of atherosclerosis.
