RT Journal Article SR Electronic T1 Radioiodinated BMIPP as a potential probe for hepatic fatty acid metabolism: Evaluation in mice at different feeding status JF Journal of Nuclear Medicine JO J Nucl Med FD Society of Nuclear Medicine SP 1209 OP 1209 VO 54 IS supplement 2 A1 Yamasaki, Kazuaki A1 Zhao, Songji A1 Nishimura, Mie A1 Zhao, Yan A1 Yu, Wenwen A1 Shimizu, Yoichi A1 Nishijima, Ken-ichi A1 Tamaki, Nagara A1 Takeda, Hiroshi A1 Kuge, Yuji YR 2013 UL http://jnm.snmjournals.org/content/54/supplement_2/1209.abstract AB 1209 Objectives Alteration of fatty acids (FA) metabolism in the liver leads to various diseases including hepatic steatosis. Therefore, understanding of hepatic FA metabolism is useful for evaluation of the diseases. A FA analog, 123I-15-(p-iodophenyl)-3(R,S)-methylpentadecanoic acid (123I-BMIPP) is widely used for the diagnosis of cardiac FA metabolism, however the intrahepatic kinetics has not been investigated in detail. Thus, in order to clarify potentials of 123I-BMIPP for imaging hepatic FA metabolism, we determined hepatic distribution/metabolism of 125I-BMIPP in mice at various metabolic status induced by fasting. Methods Fed or fasted (6, 12, and 24 h fasting) mice were injected with 125I-BMIPP. Radioactivity in the liver was measured at 1, 5, 10, 30, 60 and 120 min after the injection (n=5 in each time point). Lipid fraction was extracted from the liver by the Folch method, and radioactivity in the lipid fraction (e.g. unchanged 125I-BMIPP and triglyceride (TG)) was analyzed by thin-layer chromatography. Results The hepatic radioactivity in the fasted groups was higher than in the fed group, and this tendency was depending on the fasting time (AUC: 35, 45, 56, 59 (%ID/g/kg)×min for fed, 6, 12, 24 h-fasting). Radioactivity in the TG fraction was also higher in the fasted groups than the fed group (AUC: 6, 12, 31, 37 (%ID/g/kg)×min for fed, 6, 12, 24 h-fasting). It is known that FA released from adipose tissues can be re-esterified to produce TG in the liver under fasting when influx of FA exceeds hepatic oxidation capacity, which may explain the present results. Conclusions Hepatic distribution of 125I-BMIPP was increased by fasting and further elevation was seen by extension of fasting time. Increased storage as TG by fasting may be the reason for the difference. 125I-BMIPP can detect changes in hepatic FA metabolism induced by fasting, indicating potentials 123I-BMIPP for imaging hepatic FA metabolism.