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Author Graves, S. ♦ Hernandez, R. ♦ England, C. ♦ Valdovinos, H. ♦ Jeffery, J. ♦ Barnhart, T. ♦ Cai, W. ♦ Nickles, R.
Source United States Department of Energy Office of Scientific and Technical Information
Content type Text
Language English
Subject Keyword RADIOLOGY AND NUCLEAR MEDICINE ♦ APPLIED LIFE SCIENCES ♦ ANIONS ♦ BIOMEDICAL RADIOGRAPHY ♦ IMAGES ♦ INSULIN ♦ ION CYCLOTRON-RESONANCE ♦ ION EXCHANGE ♦ ION EXCHANGE CHROMATOGRAPHY ♦ MEV RANGE 10-100 ♦ PANCREAS ♦ POSITRON COMPUTED TOMOGRAPHY ♦ UPTAKE
Abstract Purpose: To image β-cells noninvasively using radio-manganese PET and to develop efficient small cyclotron production of {sup 51}Mn (t1/2=46m, β{sup +}=97%) and {sup 52}Mn (t1/2=5.6d, β{sup +}=29%). Methods: {sup 51}Mn and {sup 52}Mn were produced by 16 MeV proton irradiation (GE PETtrace) of electrodeposited {sup 54}Fe on silver and Cr metal pressed into a silver disc, respectively. {sup 51}Mn was radiochemically isolated from target material by anion exchange chromatography and {sup 52}Mn was isolated by ethanolic anion exchange trap-and-release. A final injectable product of {sup 51}Mn{sup 2+} or {sup 52}Mn{sup 2+} was obtained in 0.01M pH 6.0 NaOAc. To assess pancreatic uptake, fasted ICR mice were administered and intravenous bolus or infusion of {sup 52}Mn{sup 2+}. Additionally, to demonstrate the correlation between β-cell function and {sup 52}Mn{sup 2+} pancreatic uptake, prior to tracer administration groups of ICR mice were administered glibenclamide (5mg/kg) and diazoxide (20 mg/kg) as an insulin release stimulator and blocker, respectively. To validate PET ROI quantification, ex vivo biodistribtution studies were conducted on each subject after the final imaging time-point. Results: Dynamic PET data using a left atrium ROI revealed that {sup 52}Mn{sup 2+} cleared from the blood with a 10 second half-life. Significant uptake was seen in the pancreas (approximately 20% ID/g, SUVmean= 5.5), liver, kidneys, intestine, heart, and thyroid. Pancreatic uptake was found to be highly sensitive to volatile anesthesia administration (p=0.0002), insulin release stimulation by glibenclamide (p=0.017), and by insulin release inhibition by diazoxide (p=0.046). Excellent agreement was found between in vivo PET ROI quantification and ex vivo biodistribution measurements. Conclusion: This work demonstrates the feasibility of using radiomanganese-PET for measuring functional β-cell mass in vivo. The decay characteristics and dosimetric properties of {sup 51}Mn are well suited for clinical PET, which will allow for rapid translation and application.
ISSN 00942405
Educational Use Research
Learning Resource Type Article
Publisher Date 2016-06-15
Publisher Place United States
Journal Medical Physics
Volume Number 43
Issue Number 6


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