Effect of ramipril and losartan on atherosclerosis early formation in high fat diet-fed hamsters

Objective: To investigate the effect of ramipril and losartan on the early stages in the development of atherosclerosis in Golden hamsters. Methods: The animals were fed a high fat diet containing 10% coconut oil and 0.05% cholesterol, and were treated with ramipril （2mg·kg^-1） or losartan （10mg·kg^-1） or a combination of ramipril plus losartan by gavage for 12 weeks. Blood pressure, plasma lipids, aortic fatty streak size and hepatic cholesterol concentration were analysed. Results: Ramipril and losartan significantly reduced mean arterial pressure both alone or in combination when compared to the untreated group （P＜0.01）. Hepatic tissue total cholesterol content was reduced by ramipril （P＜0.05） or losartan （P＜0.001） alone or in combination （P＜0.001） when compared to the group receiving high fat diet. Ramipril markedly reduced plasma triglyceride level （P＜0.05） and the combination of ramipril plus losartan increased plasma HDL-cholesterol levels （P＜0.05）. Furthermore, the fatty streak area of aortic arch as reduced by ramipril （22.2%）, losartan （9.4 %） and a combination of ramipril plus losartan （46.8%）, but these changes were not significant when compared with the group receiving high fat diet. Conclusions: These findings suggest that ramipril and losartan can reduce atherosclerosis formation, in part due to lowered blood pressure and altered lipid metabolism.