Mn Distribution in rat hippocampus: Correlative use of Synchrotron X-Ray Microprobe and MEMRI

INTRODUCTION It has been discovered that manganese (Mn) enhanced magnetic resonance imaging (MEMRI) can be used to trace neuronal connections activated following specific stimulation or to enhance the brain region cytoarchitecture such as the hippocampus and the olfactory bulb. The biological basis for the movement of Mn in tissues and its cellular distribution are still unclear. Furthermore, a major drawback to the use of Mn as an MRI contrast agent is its cellular toxicity. It raises the interest of identifying the brain cells targeted by Mn, in order to get better insights in MEMRI mechanisms and possibly to drive the development of new Mn-based contrast agents for pre-clinical applications.