Abstract 5823: 125I-anti H-FABP Antibody Imaging in Acute Reperfusion Ischemia in Rat Heart
Heart-type fatty acid binding protein (H-FABP) plays an important role in fatty acid metabolism, is characterized by high specificity and rapid appearance from myocardium. Higuchi T. reported that 123I-BMIPP (BMIPP) uptake was higher in ischemia reperfusion area compared to perfusion tracer, indicating that transient metabolic activation was induced in early phase of acute reperfusion ischemia. The objective of this study was to clarify H-FABP expression in ischemic area using radio-labeled anti H-FABP antibody, and correlation with fatty acid metabolism. Wistar Rats were allotted to ischemia non-reperfused group (IG; n= 4), ischemia-reperfused group (RG; n= 4) and sham-operated group (n= 4). Ligation of left descending coronary artery (LAD) was performed. 20min of ischemia was followed by 60min of reperfusion for RG. 125I-anti H-FABP antibody (anti-FABP), BMIPP and 99mTc-sestamibi (MIBI) was injected intravenously. Digital autoradiogram was performed using μ-imager®. Radioactive ratio of LAD related area to inferior (normal) area (target uptake ratio= TUR) was generated. In sham, no visually detectable accumulation was observed on the anti-FABP image, and TURMIBI and TURBMIPP were equivalent to 1. In IG, TURMIBI and TURBMIPP were remarkably low (0.12± 0.01, 0.24± 0.07). In RG, TURMIBI was significantly lower (0.20± 0.03, p< 0.05), but TURBMIPP was significantly higher (2.78± 1.28, p< 0.05) compared to sham. Anti-FABP showed markedly higher ratio in the reperfused area in RG(3.43± 0.73, vs sham p< 0.05). Anti-FABP accumulated specifically in reperfused area, and it accorded to the area where fatty acid metabolism was activated.