Abstract
123I-3-iodo-alpha-methyl-L-tyrosine (123I-L-AMT) was selected and its characteristics on pancreas accumulation, metabolic selectivity and metabolic stability of125I-L-AMT were studied. The studies on rat tissue slice as well as mouse biodistribution proved very high accumulation of125I-labeled L-AMT in the pancreas, which was remarkably inhibited by the active transport inhibitor, ouabain.125I-L-AMT does not enter into protein synthesis and general amino acid catabolism. Moreover,125I-L-AMT was very stable against enzymatic deiodination. Thus, the above studies indicated that the123I-labeled L-AMT was an “artificial amino acid” radiopharmaceutical to be used for the selective measurement of the membrane amino acid transport rate in the pancreas.
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Kawai, K., Fujibayashi, Y., Yonekura, Y. et al. An artificial amino acid radiopharmaceutical for single photon emission computed tomographic study of pancreatic amino acid transports123I-3-iodo-alpha-methyl-L-tyrosine. Ann Nucl Med 6, 169–175 (1992). https://doi.org/10.1007/BF03178309
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DOI: https://doi.org/10.1007/BF03178309