RT Journal Article SR Electronic T1 Evaluation of Fatty Acid Metabolism in Hearts After Ischemia–Reperfusion Injury Using a Dual-Isotope Autoradiographic Approach and Tissue Assay for Metabolites of Tracer JF Journal of Nuclear Medicine JO J Nucl Med FD Society of Nuclear Medicine SP 160 OP 164 VO 46 IS 1 A1 Igarashi, Norio A1 Nozawa, Takashi A1 Fujii, Nozomu A1 Kato, Bun-ichi A1 Nonomura, Makoto A1 Matsuki, Akira A1 Nakadate, Teruo A1 Igawa, Akihiko A1 Asanoi, Hidetsugu A1 Inoue, Minoru A1 Inoue, Hiroshi YR 2005 UL http://jnm.snmjournals.org/content/46/1/160.abstract AB We investigated whether changes in myocardial uptake of fatty acid tracer after reperfusion following transient myocardial ischemia were closely related to alterations in intracellular fatty acid oxidation. Methods: Using a fatty acid tracer of 131I- and 125I-labeled 15-(p-iodophenyl)-9-methylpentadecanoic acid (9MPA), the myocardial uptake and metabolites were determined by dual-tracer autoradiography and thin-layer chromatography in rats 3 or 14 d after reperfusion following 5 or 15 min of ischemia induced by coronary artery ligation. Results: 9MPA metabolites processed via β-oxidation were lower in the ischemic region (IR) than in non-IR 3 d after 5 min of ischemia, despite no reduction of tracer uptake in IR. Oxidation of 9MPA was recovered 14 d after 15 min of ischemia in association with normalization of tracer uptake in IR, whereas both uptake and oxidation of 9MPA were markedly impaired 3 d after 15 min of ischemia, accompanied by slow clearance of myocardial tracer. Conclusion: Normal uptake of fatty acid tracer early after reperfusion does not always imply preserved intracellular fatty acid oxidation. However, reduction of tracer uptake might reflect impaired fatty acid oxidation.