Nitrotyrosine as a new marker for endogenous nitrosation and nitration of proteins

Food Chem Toxicol. 1990 Sep;28(9):647-52. doi: 10.1016/0278-6915(90)90173-k.


3-Nitrotyrosine (NTYR) in tissue or blood proteins was evaluated as a possible exposure marker for exogenous and endogenous nitrosating or nitrating agents. A sensitive and selective method for analysing NTYR by gas chromatography with a thermal energy analyser (GC-TEA) was developed. Using this method, a number of kinetic studies were carried out. It was found that free and protein-bound tyrosine residues easily react with nitrating/nitrosating agents to yield NTYR. NTYR formation in vivo showed a dose-dependent increase in NTYR in both plasma proteins and haemoglobin obtained from rats 24 hr after ip injection of various doses (0.5-2.5 mumol/rat) of tetranitromethane. Major urinary metabolites of NTYR, given orally to rats, were isolated and identified as 3-nitro-4-hydroxyphenylacetic acid (NHPA) and 3-nitro-4-hydroxyphenyllactic acid (NHPL). About 44% and 5% of the oral dose of NTYR (100 micrograms/rat) was excreted as NHPA and NHPL, respectively. Eleven 24-hr human urine samples were analysed for NHPA by GC-TEA after ethyl acetate extraction and HPLC purification: quantities ranging from 0 to 7.9 micrograms/24 hr, mean +/- SD 2.8 +/- 2.3 (n = 11) were detected (detection limit 0.2 micrograms/litre). NTYR in proteins or its metabolites in urine can be readily analysed by GC-TEA as a new/additional marker for endogenous nitrosation and nitration.

MeSH terms

  • Animals
  • Blood Proteins / metabolism
  • Gas Chromatography-Mass Spectrometry
  • Humans
  • Kinetics
  • Male
  • Nitrosamines / metabolism
  • Nitrosation
  • Rats
  • Tetranitromethane / metabolism
  • Tyrosine / analogs & derivatives*
  • Tyrosine / analysis
  • Tyrosine / blood
  • Tyrosine / metabolism


  • Blood Proteins
  • Nitrosamines
  • 3-nitrotyrosine
  • Tyrosine
  • nitrosoproline
  • Tetranitromethane