title: Manganese-enhanced magnetic resonance imaging (MEMRI): methodological and practical considerations.
abstract: Manganese-enhanced MRI (MEMRI) is being increasingly used for MRI in animals due to the unique T1 contrast that is sensitive to a number of biological processes. Three specific uses of MEMRI have been demonstrated: to visualize activity in the brain and the heart; to trace neuronal specific connections in the brain; and to enhance the brain cytoarchitecture after a systemic dose. Based on an ever-growing number of applications, MEMRI is proving useful as a new molecular imaging method to visualize functional neural circuits and anatomy as well as function in the brain in vivo. Paramount to the successful application of MEMRI is the ability to deliver Mn2+ to the site of interest at an appropriate dose and in a time-efficient manner. A major drawback to the use of Mn2+ as a contrast agent is its cellular toxicity. Therefore, it is critical to use as low a dose as possible. In the present work the different approaches to MEMRI are reviewed from a practical standpoint. Emphasis is given to the experimental methodology of how to achieve significant, yet safe, amounts of Mn2+ to the target areas of interest.
authors.affiliation: Laboratory of Functional and Molecular Imaging, National Institutes of Neurological Disorders and Stroke, Bethesda, MD 20892-1065, USA. SilvaA@ninds.nih.gov
authors.forename: Afonso C
authors.initials: AC
authors.lastname: Silva
authors.forename: Jung Hee
authors.initials: JH
authors.lastname: Lee
authors.forename: Ichio
authors.initials: I
authors.lastname: Aoki
authors.forename: Alan P
authors.initials: AP
authors.lastname: Koretsky
mesh_terms: D000818:Animals; D001921:Brain / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism; D003287:Contrast Media / Q000008:administration & dosage* / Q000009:adverse effects / Q000493:pharmacokinetics; D004305:Dose-Response Relationship, Drug; D006321:Heart / Q000187:drug effects; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008345:Manganese / Q000008:administration & dosage / Q000009:adverse effects / Q000493:pharmacokinetics; D009206:Myocardium / Q000166:cytology* / Q000378:metabolism; D009434:Neural Pathways / Q000166:cytology* / Q000378:metabolism
chemical_list: D003287:Contrast Media; D008345:Manganese