Harnessing axonal transport to map reward circuitry: Differing brain-wide projections from medial prefrontal cortical domains

Abstract

Graphical AbstractTract tracing after MnCl2 stereotactic intracerebral injection is performed by time-lapse MRI in living mice, based on harnessing the intracellular axonal transport machinery, kinesin and microtubules. Volumes of statistically significant, Mn(II)-dependent, image enhancements report on distal accumulations brain wide that can be measured segment-wise for statistical comparisons of the relative strength of the projection contacts. Targets of neuronal projections from the medial prefrontal cortex differ between anterior cingulate (ACA, red) and infralimbic-prelimbic (IL/PL, blue) areas. While neurons in ACA project to central amygdala, posterior hypothalamic regions, periaqueductal gray, dorsal raphe, and locus coeruleus; those in IL/PL project to basolateral amygdala, anterior hypothalamic subsegments, central superior raphe and pons.