Benjamin Waghorn1,2, Yuhui Yang1, Akemichi Baba3, Toshio Matsuda3, Nathan Yanasak1, Tom C.-C. Hu1,2
1Small Animal Imaging, Medical College of Georgia, Augusta, GA, USA; 2NRE and Medical Physics Programs, Georgia Institute of Technology, Atlanta, GA, USA; 3Graduate School of Pharmaceutical Sciences, Osaka University, Osaka, Japan
Intracellular calcium (Ca2+) overloading that occurs via the Na+/Ca2+ exchanger (NCX) during myocardial ischemia-reperfusion is known to exacerbate injuries. This study demonstrates that T1 mapping manganese-enhanced MRI in a murine model can be used to quantify the temporal rate of change of myocardial relaxation rates (∆R1) following infusion of MnCl2. Inhibiting the NCX with SEA0400 demonstrates a reduction in the rate of ∆R1 washout. This technique could potentially be employed to assess Mn2+ efflux mechanisms and rates in vivo. Studying Mn2+ efflux using this protocol provides a pre-clinical model for examining alterations in Ca2+ efflux in monitoring disease progression.