Timelapse Mn++ Enhanced MRI in the living brain.
Jacobs R, Tyszka J, Zhang X, Hiltner T, Bearer E
California Institute of Technology
Neuronal transport has never been directly imaged in the living brain. Transport delivers molecules to distant sites and is useful for tracing neuronal pathways by histology. MEMRI allows investigation of transport parameters and tract tracing in vivo. We injected Mn++ into (1) the vitreous of the eye and (2) the optic chiasm and monitored its effect on neuronal activity by VEP. Mn++ transport was imaged over time (every 6min for 2hr) by T1-weighted MR and sighted versus blind mice compared. Mn++ transiently inhibits VEP, rates suggest transport along different intracellular pathways that differ for anterograde and retrograde directions.