Objective: To compare the effects of perindopril and enalapril on the development of atherosclerotic lesions in ApoE knockout mice.
Methods: ApoE knockout mice were treated with perindoprilor (1.5 mg.kg(-1).d(-1), n = 20), enalapril (7.5 mg.kg(-1).d(-1), n = 20) or saline (0.2 ml saline/d, n = 20) per gavage for 20 weeks. Blood pressure and lipids were measured at the study end. Aortic root atherosclerotic plaque was then quantified and the content of collagen and the size of lipid core in the plaque assessed. Cryostat sections were used to quantify the expressions of monocyte/macrophage-2 (MOMA-2), intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) and matrix metalloproteinases-9 (MMP-9) in the plaque by immunofluorescence method.
Results: Blood pressure and lipid profiles were similar among different groups. Compared with control group, the plaque areas of perindopril group and enalapril group displayed significantly decrease (25.33% and 22.86%, respectively, both P < 0.01). However, no significant different were observed in the plaque size between the different ACE inhibitors groups. Perindopril group and enalapril group also significantly decreased the size of lipid core (52.98% and 38.98%, respectively, both P < 0.01) and the expression of MOMA-2 (88.38% and 52.16%, respectively, both P < 0.01), ICAM-1 (80.87% and 49.59%, respectively, both P < 0.01), VCAM-1 (77.56% and 56.44%, respectively, both P < 0.01) and MMP-9 (86.93% and 55.56%, respectively, both P < 0.01), and increased the plaque collagen content (298.36% and 168.14%, respectively, both P < 0.01) and the effects of perindopril was superior to those of enalapril (all P < 0.05).
Conclusions: ACE inhibitors significantly suppressed tissue inflammation and attenuated the development of atherosclerosis in ApoE knockout mice independent of their effects on the lipid and blood pressure. Perindopril is superior to enalapril in stabilizing the plaques and has similar effect on reducing the plaque size as that of enalapril.