Premium
The slow metabolism of L‐[2‐ 18 F]‐fluorophenylalanine in rat
Author(s) -
Murakami M.,
Takahashi K.,
Kondo Y.,
Mizusawa S.,
Nakamichi H.,
Sasaki H.,
Hagami E.,
Iida H.,
Kanno I.,
Miura S.,
Itoh I.,
Uemura K.
Publication year - 1989
Publication title -
journal of labelled compounds and radiopharmaceuticals
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.432
H-Index - 47
eISSN - 1099-1344
pISSN - 0362-4803
DOI - 10.1002/jlcr.2580270303
Subject(s) - chemistry , phenylalanine , metabolism , amino acid , tritium , radiochemistry , biochemistry , physics , nuclear physics
The stability of L‐[2‐ 18 F]‐fluorophenylalanine (2‐[ 18 F]‐Phe) was compared with that of natural amino acid, L‐[2,6‐ 3 H]‐Phenylalanine (2,6‐[ 3 H]‐Phe). The mixture of 2‐[ 18 F]‐ and 2,6‐[ 3 H]‐Phe was injected to Wistar rats. The separated arterial plasma was followed by acid treatment and chromatographical analysis. The plasma [ 18 F]‐ and [ 3 H]‐radioactivities decreased with the time and showed the lowest value at 20 min after injection. After that, [ 3 H]‐radioactivity increased significantly up to 60 min, while [ 18 F] ‐ radioactivity remained at the lowest level. The [ 3 H]‐ and [ 18 F] ‐ radioactive macromolecules appeared in the plasma at 10 and 20 min, respectively. In the acid soluble fractions of the plasma and the brain at 60 min, more than 80% of [ 18 F] ‐ radioactivity existed as 2‐[ 18 F] ‐ Phe, while 2,6 ‐ [ 3 H] ‐ Phe was less than 15%. These data suggest the slow metabolism of 2 ‐ [ 18 F] ‐ Phe as compared with that of natural Phe. In conclusion, 2 ‐ [ 18 F] ‐ Phe is suitable to the compartment analysis using positron emission tomography especially at the process of amino acid transport to the brain due to its stability for the period necessary to kinetic analysis.