ABSTRACT

This chapter outlines the applications, including feasibility studies, of the in vivo electron paramagnetic resonance (EPR) and EPR-imaging (EPRI) techniques. The mouse was anesthetized with its tail placed into the active region of the L-band loop-gap resonator where a sizeable EPR signal was reported. To date, however, the only success in EPR experiments has come from ex vivo experiments where signals have been observed from either isolated blood or the perfusion medium from isolated Langendorf perfused hearts. The challenge to in vivo EPRI has been the possibility of observing some medically relevant tissue, tumor, or disease state. The feasibility of EPR measurements in vivo is promising. The in vivo observation of most transition metal-ions signals has been unsuccessful to date. The first experiments involving an in vivo model for a biological system with nitroxides was reported by Berliner and Fujii in 1985. The cellular studies discussed above may be difficult to extrapolate to true in vivo situations.