Dataset Information

Human Biodistribution and Radiation Dosimetry of the P-Glycoprotein Radiotracer [¹¹C]Metoclopramide.

ABSTRACT:

Purpose

To assess in healthy volunteers the whole-body distribution and dosimetry of [¹¹C]metoclopramide, a new positron emission tomography (PET) tracer to measure P-glycoprotein activity at the blood-brain barrier.

Procedures

Ten healthy volunteers (five women, five men) were intravenously injected with 387?±?49 MBq of [¹¹C]metoclopramide after low dose CT scans and were then imaged by whole-body PET scans from head to upper thigh over approximately 70 min. Ten source organs (brain, thyroid gland, right lung, myocardium, liver, gall bladder, left kidney, red bone marrow, muscle and the contents of the urinary bladder) were manually delineated on whole-body images. Absorbed doses were calculated with QDOSE (ABX-CRO) using the integrated IDAC-Dose 2.1 module.

Results

The majority of the administered dose of [¹¹C]metoclopramide was taken up into the liver followed by urinary excretion and, to a smaller extent, biliary excretion of radioactivity. The mean effective dose of [¹¹C]metoclopramide was 1.69?±?0.26 ?Sv/MBq for female subjects and 1.55?±?0.07 ?Sv/MBq for male subjects. The two organs receiving the highest radiation doses were the urinary bladder (10.81?±?0.23 ?Gy/MBq and 8.78?±?0.89 ?Gy/MBq) and the liver (6.80?±?0.78 ?Gy/MBq and 4.91?±?0.74 ?Gy/MBq) for female and male subjects, respectively.

Conclusions

[¹¹C]Metoclopramide showed predominantly renal excretion, and is safe and well tolerated in healthy adults. The effective dose of [¹¹C]metoclopramide was comparable to other ¹¹C-labeled PET tracers.

SUBMITTER: Bauer M

PROVIDER: S-EPMC7910245 | biostudies-literature | 2021 Apr

REPOSITORIES: biostudies-literature

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Publications

Human Biodistribution and Radiation Dosimetry of the P-Glycoprotein Radiotracer [<sup>11</sup>C]Metoclopramide.

Bauer Martin M Barna Sandra S Blaickner Matthias M Prosenz Konstantin K Bamminger Karsten K Pichler Verena V Tournier Nicolas N Hacker Marcus M Zeitlinger Markus M Karanikas Georgios G Langer Oliver O

Molecular imaging and biology 20210122 2

<h4>Purpose</h4>To assess in healthy volunteers the whole-body distribution and dosimetry of [<sup>11</sup>C]metoclopramide, a new positron emission tomography (PET) tracer to measure P-glycoprotein activity at the blood-brain barrier.<h4>Procedures</h4>Ten healthy volunteers (five women, five men) were intravenously injected with 387 ± 49 MBq of [<sup>11</sup>C]metoclopramide after low dose CT scans and were then imaged by whole-body PET scans from head to upper thigh over approximately 70 min. ...[more]

PMID: 33481175

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Dataset Information

Human Biodistribution and Radiation Dosimetry of the P-Glycoprotein Radiotracer [¹¹C]Metoclopramide.

Purpose

Procedures

Results

Conclusions

Publications

Human Biodistribution and Radiation Dosimetry of the P-Glycoprotein Radiotracer [<sup>11</sup>C]Metoclopramide.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

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Dataset Information

Human Biodistribution and Radiation Dosimetry of the P-Glycoprotein Radiotracer [11C]Metoclopramide.

Purpose

Procedures

Results

Conclusions

Publications

Human Biodistribution and Radiation Dosimetry of the P-Glycoprotein Radiotracer [<sup>11</sup>C]Metoclopramide.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets

Human Biodistribution and Radiation Dosimetry of the P-Glycoprotein Radiotracer [¹¹C]Metoclopramide.