The presence of 4-hydroxyphenylacetic acid in human saliva and the possibility of its nitration by salivary nitrite in the stomach

FEBS Lett. 2002 May 8;518(1-3):116-8. doi: 10.1016/s0014-5793(02)02659-5.

Abstract

Human saliva contained 4-hydroxyphenylacetic acid (HPA) (2-10 microM) and nitrite (60-300 microM). HPA was nitrated to 4-hydroxy-3-nitrophenylacetic acid (NO2HPA) when HPA and sodium nitrite were mixed at pH 1.0. NO2HPA was also formed when saliva was incubated under acidic conditions. These results suggest that salivary HPA is nitrated to NO2HPA when saliva is swallowed into the stomach.

MeSH terms

  • Gastric Mucosa / metabolism
  • Humans
  • Hydrogen-Ion Concentration
  • Nitrites / analysis
  • Nitrophenols / metabolism*
  • Phenylacetates / analysis*
  • Phenylacetates / metabolism*
  • Saliva / chemistry*
  • Saliva / metabolism
  • Sodium Nitrite / metabolism

Substances

  • Nitrites
  • Nitrophenols
  • Phenylacetates
  • 4-hydroxy-5-nitrophenyl acetic acid
  • 4-hydroxyphenylacetic acid
  • Sodium Nitrite