Satoshi Yasuda a , Kenjiro Ikuta c , Toyokazu Uwatoku b , Keiji Oi b , Kohtaro Abe b , Fuminori Hyodo d , Kengo Yoshimitsu e , Kohtaro Sugimura f , Hideo Utsumi d , Yoshiki Katayama c , Hiroaki Shimokawa a
16 October 2007
Background: Magnetic resonance imaging (MRI) contrast agents that specifically detect atherosclerotic plaque may be useful for the noninvasive detection of the plaque. We have recently developed a new contrast agent, Evans blue-DTPA-gadolinium (EB-DTPA-Gd), which selectively accumulates vascular lesions with endothelial removal. In this study, we examined whether EB-DTPA-Gd is also useful for in vivo imaging of atherosclerotic plaques. Methods: We used male apolipoprotein-E-deficient (ApoE–/–) mice of different ages (3, 6 and 12 months old) and age-matched male wild-type mice. After a single intravenous administration of EB-DTPA-Gd (160 µ M/kg body weight), MRI T<sub>1</sub> signal was obtained in vivo. Results: Increased signal intensity in the aortic wall was noted within 10–20 min after intravenous injection of EB-DTPA-Gd and was maintained for 30 min. The MRI enhancement in the aorta of ApoE–/– mice was increased in accordance with age, whereas no such enhancement was noted in wild-type mice. Histological examination demonstrated that there was a topological correlation between the site of MRI enhancement and that of atherosclerotic plaque. Conclusions: These results indicate that EB-DTPA-Gd is a useful MRI contrast medium for the in vivo detection of atherosclerotic plaques.