Synthesis and tissue biodistribution of [omega-11C]palmitic acid. A novel PET imaging agent for cardiac fatty acid metabolism.
In order to diagnose patients with medium-chain acyl-CoA dehydrogenase deficiency with a noninvasive diagnostic technique such as positron emission tomography, we have developed a synthesis of [omega-11C]palmitic acid. The radiochemical synthesis was achieved by coupling an alkylfuran Grignard reagent (7) with [11C]methyl iodide, followed by rapid oxidative cleavage of the furan ring to the carboxylate using ruthenium tetraoxide. Tissue biodistribution studies in rats comparing [omega-11C]palmitic acid and [1-11C]palmitic acid show that the %ID/g and %ID/organ in the heart tissue after administration of [omega-11C]palmitic acid is approximately 50% greater than after administration of [1-11C]palmitic acid, due to the diminished metabolism of the [omega-11C]palmitic acid. These studies show as well, low uptake in nontarget tissues (blood, lung, kidney, and muscle). PET images of a dog heart obtained after administration of [omega-11C]-and [1-11C]palmitic acid show virtually identical uptake and distribution in the myocardium. The differing cardiac washout of labeled palmitates measured by dynamic PET studies may allow diagnosis of disorders in cardiac fatty acid metabolism.
Buckman
B O
BO
Department of Chemistry, University of Illinois, Urbana 61801.
VanBrocklin
H F
HF
Dence
C S
CS
Bergmann
S R
SR
Welch
M J
MJ
Katzenellenbogen
J A
JA
D042964:Acyl-CoA Dehydrogenase; D044944:Acyl-CoA Dehydrogenases / Q000172:deficiency; D000818:Animals; D002250:Carbon Radioisotopes; D003287:Contrast Media; D004285:Dogs; D005260:Female; D006321:Heart / Q000000981:diagnostic imaging; D006801:Humans; D008052:Lipid Metabolism, Inborn Errors / Q000175:diagnosis; D009206:Myocardium / Q000378:metabolism*; D010084:Oxidation-Reduction; D019308:Palmitic Acid; D010169:Palmitic Acids / Q000138:chemical synthesis / Q000378:metabolism / Q000493:pharmacokinetics*; D011854:Radiochemistry; D051381:Rats; D017207:Rats, Sprague-Dawley; D014018:Tissue Distribution; D014055:Tomography, Emission-Computed
D002250:Carbon Radioisotopes; D003287:Contrast Media; D010169:Palmitic Acids; D019308:Palmitic Acid; D044944:Acyl-CoA Dehydrogenases; D042964:Acyl-CoA Dehydrogenase