Comparative evaluation of fatty acids labeled with C-11, Cl-34m, Br-77, and I-123 for metabolic studies of the myocardium: concise communication.

Various long-chain fatty acids have been labeled with C-11, Cl-34m, Br-77, and I-123 and evaluated for their potential application in measuring myocardial metabolism in vivo. Comparative studies of the kinetics of accumulation and clearance from the heart muscle of mice indicate that the extraction of omega-halofatty acids is more efficient than that of alpha-halofatty acids. Among the omega-halofatty acids, the highest uptake is observed for the 17-iodoheptadecanoic acid, which shows an extraction behavior almost identical to that of [1-11C] palmitic acid, although with a higher radioactivity level in blood due to the release of free iodide.