RESUMO
Purpose@#2-Deoxy-2-[18F] fluoro-d-glucose positron emission tomography (18F-FDG-PET) is a less-invasive and widely useddiagnostic tool for detection of malignant tumors. However, prolonged retention of 18F-FDG in the body increases radiationexposure. This study evaluated the effect of oral administration of milk and ursodeoxycholic acid (UDCA) in terms of reducingradiation exposure by 18F-FDG. @*Methods@#18F-FDG radioactivity was measured using a digital γ counter in the whole body and in various organs of rats after oraladministration of milk andmilk plusUDCA (milk + UDCA).Western blotting was performed to measure the expression levels ofG6Pase, HK 2, CREB, FoxO1, and PGC-1α in the brain, liver, small intestine, and large intestine to assess the mechanismunderlying the reduction in radiation exposure from 18F-FDG by oral administration of milk and UDCA. @*Results@#We found a significant reduction in 18F-FDG radioactivity in the whole body and in the brain, liver, and small and largeintestines. Expression of G6Pase was significantly increased in the above-mentioned organs in the milk and milk + UDCAgroups. Expression of HK 2 was significantly decreased in the brain and small intestine in the milk and milk + UDCA groups.CREB, FoxO1, and PGC-1α expression levels in the brain, liver, and small intestine were increased in the milk and milk +UDCA groups. However, expression of PGC-1α in the large intestine in the milk and milk + UDCA groups was significantlydecreased compared with that in the control group. @*Conclusion@#The present study demonstrated that administration of milk and UDCA increased G6Pase expression levels and 18FFDGrelease from the tissue. These results suggest milk and UDCA could be used to reduce radiation exposure from 18F-FDGafter image acquisition. The mechanisms underpinning this phenomenon should be explored in a human study.