Abstract 376: Platelet Depletion Accelerates the Vulnerability of Early Atherosclerosis in Apolipoprotein E-Deficient Mice
Objective. Platelets were presented in human atherosclerotic plaque. The function of platelets in the development of atherosclerosis is far poorly defined. We addressed the role of platelets in mediating atherosclerosis formation.
Methods and Results. Apolipoprotein E-deficient mice (ApoE-/-) were fed with a high-fat Western diet for 12 weeks. Thrombocytopenia was induced by intraperitoneal (i.p.) injections every 3 days with mouse of the platelet-depleting antibody to ApoE-/- mice from 8 weeks. Until the experimental endpoint, atherosclerotic lesion in the aorta and aortic roots were quantified after staining. Size of atherosclerotic plaque in aortic root did not differ between platelet-depleted mice and controls (134±13.1 μm2 [x103] vs 124±11.4 μm2 [x103]; P>0.5). Plasma cholesterol did not differ between groups. However, atherosclerotic lesions of platelet-depleted mice exhibited thinner fibrous caps (62.5±9.2 μm vs. 323±63 μm; P<0.05) and larger necrotic cores (19.5±4.9 μm2 [x103] vs. 4.8±0.8 μm2 [x103]; P<0.05) than controls. Furthermore, compared with controls, platelet-depleted AopE-/- mice promoted significantly increased number of macrophage infiltration into the atherosclerotic lesions.
Conclusion. Our results suggest that platelet depletion promotes atherosclerotic plaque instability in the development of early atherosclerosis, likely though the macrophage infiltration. These results offer important insights into the in vivo function of platelet, and help to explain the association between enhanced platelet deposition and thrombotic complications of atherosclerosis, such as myocardial infarction.
- © 2013 by American Heart Association, Inc.