PET imaging of leptin biodistribution and metabolism in rodents and primates.
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ABSTRACT:
SUBMITTER: Ceccarini G
PROVIDER: S-EPMC2867490 | biostudies-literature | 2009 Aug
REPOSITORIES: biostudies-literature
Publications
PET imaging of leptin biodistribution and metabolism in rodents and primates.
Ceccarini Giovanni G Flavell Robert R RR Butelman Eduardo R ER Synan Michael M Willnow Thomas E TE Bar-Dagan Maya M Goldsmith Stanley J SJ Kreek Mary J MJ Kothari Paresh P Vallabhajosula Shankar S Muir Tom W TW Friedman Jeffrey M JM
Cell metabolism 20090801 2
We have determined the systemic biodistribution of the hormone leptin by PET imaging. PET imaging using (18)F- and (68)Ga-labeled leptin revealed that, in mouse, the hormone was rapidly taken up by megalin (gp330/LRP2), a multiligand endocytic receptor localized in renal tubules. In addition, in rhesus monkeys, 15% of labeled leptin localized to red bone marrow, which was consistent with hormone uptake in rodent tissues. These data confirm a megalin-dependent mechanism for renal uptake in vivo. ...[more]
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