Der-Yow Chen1, Kai-Hsiang Chuang2, Stephen Dodd1, Alan Koretsky1
1NINDS, National Institutes of Health, Bethesda, MD, USA; 2Singapore Bioimaging Consortium, Singapore
MEMRI can be used for neuronal tracing in the olfactory pathway. Here it is demonstrated that MEMRI visualizes the laminar structure of the olfactory system and traces layer-specific inputs to olfactory cortices. MnCl2 was infused into nostrils of rats which were imaged at several time points. Layers and boundaries of olfactory cortices were evident 48 h after infusion. Mn2+ enhancement in the superficial layer was observed earlier than the deep cell layer, consistent with known connections. Therefore, MEMRI neural tracing is specific at the level of cortical layers in the olfactory pathway, consistent with previous measurements of the somatosensory pathway.