Carolyn W. H. Wu1,2, Ning Liu3, Der-Yow Chen2, Vasalatiy Olga4, Alan P. Koretsky2, Gary L. Griffiths4, Roger B. Tootell3,5, Leslie G. Ungerleider3
1NeuroSpin, CEA de Saclay, Gif sur Yvette, Ile-de-France, France; 2NINDS, NIH, Bethesda, MD, United States; 3NIMH, NIH, Bethesda, MD, United States; 4IPDC/NHLBI, NIH, Rockville, MD, United States; 5MGH, Harvard University, Charlestown, MA, United States
A shortcoming of conventional neuroanaomy approaches to study neuronal circuitry is that it requires visualizing transported tracer in the post-mortem tissue. The goal of the study is to expand the MRI contrast media available for in vivo target-specific, mono-synaptic, neuronal tract tracing, by testing a new compound that conjugates conventional neuro-anatomical tracer CTB with GdDOTA. We show that CTBGdDOTA is a MRI neural tracer that allows in vivo visualization of mono-synaptically connected brain circuits, that is target-specific, bi-directional, very reproducible, and stable over a relatively long period of time. This agent opens the possibility for repetitive, chronic, and longitudinal studies.