NO· and ·O2-combine each other to form peroxynitrite (ONOO-) in vivo. Peroxynitrite is very cytotoxic, and it damages many biomolecules. 3-nitrotyrosine and dityrosine are two main products from the reaction of ONOO-and tyrosine. Lots of metallic ions in vivo influence the modification of tyrosine by peroxynitrite. UV-Vis and Fluorescence spectrophotometer were used to study the catalysis and inhibition of metallic ions on the production of 3-nitrotyrosine and dityrosine in vitro. Present results showed that Co?髤, Cu?髤 and Mn?髤 enhance the production of 3-nitrotyrosine, and among them Co?髤 and Mn?髤 have been reported rarely before about it. In addition, Mn?髤 inhibits the production of dityrosine to a certain extent.
