Jun-ichiro Jo1, 2, Ichio Aoki1, Tsuneo Saga1, Yasuhiko Tabata3
1Molecular Imaging Center, National Institute of Radiological Sciences, Chiba, Japan; 2Department of Biomaterials, Institute for Frontier Medical Sciences, Kyoto University , Kyoto, Japan; 3Department of Biomaterials, Institute for Frontier Medical Sciences, Kyoto University, Kyoto, Japan
The objective of this study is to design and prepare a new polymer-based contrast agent of magnetic resonance imaging (MRI) for the evaluation of therapeutic angiogenesis. Diethylenetriaminepentaacetic acid (DTPA), cyclic peptide containing an arginine-glycine-aspartic acid sequence (cRGD), and gadolinium ion (Gd3+) were introduced to dextran to obtain the dextran-based contrast agent (cRGD-dextran-DTPA-Gd). The cRGD-dextran-DTPA-Gd showed a higher longitudinal relaxivity compared with DTPA-Gd. The ischemic-angiogenic region could be clearly detected with MRI by the intravenous injection of cRGD-dextran-DTPA-Gd to mice with hindlimb ischemia. It is concluded that the cRGD-dextran-DTPA-Gd is a promising material to evaluate the therapeutic angiogenesis.