title: Labelling and metabolism of methionine-methyl-11 C.
abstract: Carbon 11 which is a 20.4 minutes half life isotope emitting positrons was used for methionine labelling on the methyl group by action of 11C-methyl-iodide on DL or L homocysteine. With the method described, 20 to 30 mCi of 11C-methyl-methionine (Specific activity 50 mCi/muM) may be obtained within 25 minutes. The 20 Mev proton beam used for 11C production was 10 muA. The metabolism of 11C methionine studied on mice shows a high uptake in pancreas and to a smaller extent in brain. On humans sequential images were obtained at the head level which allowed measurement of the uptake of the radio-labelled compound in the brain so as to study the radioactivity curve in different parts of the organ.
mesh_terms: D000328:Adult; D000818:Animals; D001921:Brain / Q000378:metabolism; D002250:Carbon Radioisotopes; D006801:Humans; D007553:Isotope Labeling / Q000379:methods; D008715:Methionine / Q000031:analogs & derivatives* / Q000378:metabolism; D051379:Mice; D008809:Mice, Inbred C3H; D009368:Neoplasm Transplantation; D009374:Neoplasms, Experimental / Q000175:diagnosis; D011877:Radionuclide Imaging
chemical_list: D002250:Carbon Radioisotopes; D008715:Methionine