Synthesis of O-[11C]Acetyl CoA, O-[11C]Acetyl-L-carnitine, and L-[11C]carnitine labelled in specific positions, applied in PET studies on rhesus monkey.
The syntheses of L-carnitine, O-acetyl CoA, and O-acetyl-L-carnitine labelled with 11C at the 1- or 2-position of the acetyl group or the N-methyl position of carnitine, using the enzymes acetyl CoA synthetase and carnitine acetyltransferase, are described. With a total synthesis time of 45 min, O-[1-11C]acetyl CoA and O-[2[11C]acetyl CoA was obtained in 60-70% decay-corrected radiochemical yield, and O-[1-11C]acetyl-L-carnitine and O-[2-11C] acetyl-L-carnitine in 70-80% yield, based on [1-11C]acetate or [2-11C]acetate, respectively. By an N-methylation reaction with [11C]methyl iodide, L-[methyl-11C]carnitine was obtained within 30 min, and O-acetyl-L-[methyl-11C]carnitine within 40 min, giving a decay-corrected radiochemical yield of 60% and 40-50%, respectively, based on [11C]methyl iodide. Initial data of the kinetics of the different 11C-labelled L-carnitine and acetyl-L-carnitines in renal cortex of anaesthetized monkey (Macaca mulatta) are presented.
Jacobson
G B
GB
Uppsala University Pet Centre, Sweden.
Watanabe
Y
Y
Valind
S
S
Kuratsune
H
H
Långström
B
B
D000105:Acetyl Coenzyme A / Q000138:chemical synthesis / Q000493:pharmacokinetics*; D000108:Acetylcarnitine / Q000138:chemical synthesis / Q000493:pharmacokinetics*; D000818:Animals; D002250:Carbon Radioisotopes; D002331:Carnitine / Q000138:chemical synthesis / Q000493:pharmacokinetics*; D007553:Isotope Labeling; D007672:Kidney Cortex / Q000378:metabolism; D008253:Macaca mulatta; D014055:Tomography, Emission-Computed
D002250:Carbon Radioisotopes; D000108:Acetylcarnitine; D000105:Acetyl Coenzyme A; D002331:Carnitine