Influence of MER-29 on Experimental Atherosclerosis of Cholesterol-Fed Cockerels

Abstract

The effects of MER-29 were studied to determine whether this drug will lower the blood lipids as well as the severity of aortic and coronary atherosclerosis of ten-week-old cockerels on a regimen of plain mash or on an atherogenic diet consisting of 2 per cent cholesterol plus 5 per cent cottonseed oil added to plain mash. After ten weeks of treatment with 12.5 mg. or 25.0 mg. per Kg. of MER-29, it was observed that the drug had no significant influence on the blood cholesterol or phospholipid levels. It was interesting to note that cockerels treated with 25.0 mg. of MER-29 per Kg. body weight, whether on plain mash or on an atherogenic diet, demonstrated an increase of aortic-atherosclerosis. The drug did not seem to lower the incidence of coronary atherosclerosis of the group fed an atherogenic diet. It appears that MER-29 causes aortic atherosclerosis of cockerels fed plain mash primarily by blocking the conversion of 24-dehydrocholesterol to cholesterol, thus increasing the amount of 24-dehydrocholesterol which was found in the aortae, as compared with little or none in the aortae of cockerels on plain mash.