A rabbit model of spontaneous thrombosis induced by lipopolysaccharide

Abstract

Aim: Inflammation plays a critical role in the development of atherosclerotic plaque, and lipopolysaccharide (LPS) is a potentially important source of inflammation. The aim of this study was to develop a rabbit model of spontaneous thrombosis mimicking the pathophysiological and morphological characteristics of atherosclerotic plaque in humans. Methods: The rabbits were randomized into four groups: group A (n = 10) received a normal diet; group B (n = 10) received a regular diet and weekly LPS injections (1 μg/kg, Escherichia coli); group C (n = 15) received a cholesterol-enriched diet before and after sustaining a balloon injury to the right common carotid artery; and group D (n = 15) was treated the same as group C in addition to receiving LPS injections. The morphological characteristics of the resulting lesions were evaluated using optical coherence tomography (OCT) and histology. Results: No significant atherosclerotic plaque was observed in groups A or B. Group D exhibited a higher incidence of spontaneous luminal thrombi than group C or B (60% vs. 20% vs. 10%, p＜ 0.05). All of the thrombi detected with OCT were confirmed on histology. A good correlation between the fibrous cap thickness and thrombus arc was obtained on OCT and the histological evaluations. Conclusions: A rabbit model of LPS-induced spontaneous thrombosis was developed in which OCT was used to follow changes in plaque morphology.