Abstract #3369

Displacement-Encoded & Manganese-Enhanced Cardiac MRI Reveal that NNOS, & Not ENOS, Plays the Dominant Role in Modulating Calcium Cycling in the Mammalian Heart

Moriel Vandsburger¹, Brent A. French², Kramer M. Christopher², Xiaodong Zhong³, Frederick H. Epstein²

¹Biological Regulation, Weizmann Institute of Science, Rehovot, Israel; ²University of Virginia, United States; ³Siemens Medical Solutions, United States

Nitric oxide (NO) is generated by both endothelial nitric oxide synthase (eNOS) and neuronal nitric oxide synthase (nNOS) in the heart, however the role of each in NO signaling is unclear. In this study, we used manganese-enhanced MRI to probe the role of each NOS in modulating L-type calcium channel function, and cine-DENSE MRI to study the role of each NOS in contractile function. Our results indicate that nNOS, and not eNOS, dominates modulation of calcium cycling in vivo.