Abstract
The in vivo dynamic behavior of ginkgolide B (GB), a terpene lactone constituent of the Ginkgo biloba extracts, in the living animal was visualized by positron emission tomographic (PET) imaging using a GB analogue labeled with the positron emitter 18F. The in vivo imaging studies, combined with ex vivo dissection experiments, reveal that GB exists in 2 forms in the body: the original GB with its lactone rings closed and a second form with one of the rings open. The original GB in plasma is taken up rapidly by various organs including the liver, the intestine and possibly the stomach. Consequently, in plasma, the proportion of the ionized form of GB increases dramatically with time. Thereafter the ratio between the 2 forms appears to shift slowly towards equilibrium. The results suggest that more attention needs to be focused on in vivo dynamics between the 2 forms of GB.
Key words
Ginkgolide B - positron emission tomography -
in vivo biodistribution of ginkgolide B - microPET -
Ginkgo biloba
- Ginkgoaceae
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Makiko Suehiro, Ph. D.
Department of Radiology
Citigroup Biomedical Imaging Center
Weill Medical College of Cornell University
516 East 72nd Street
New York
NY 10021
USA
Phone: +1-212-746-5853
Email: mas2048@med.cornell.edu
