Peroxidase-promoted oxidation and peroxidation of the serotonergic neurotoxin 5,7-dihydroxytryptamine

✍ Scribed by Diana Metodiewa; H. Brian

• Publisher: Springer
• Year: 1992
• Tongue: English
• Weight: 780 KB
• Volume: 112
• Category: Article
• ISSN: 0300-8177
• DOI: 10.1007/bf00229641

✦ Synopsis

Spectral data provide the first evidence that lactoperoxidase, a model enzyme for most mammalian peroxidases, catalyzed the one-electron oxidation and/or peroxidation of 5,7-dihydroxytryptamine. This process correlates with the production of superoxide radicals as is evident from the observed inhibitory effect of superoxide dismutase on product formation. 5,7-Dihydroxytryptamine is a classical peroxidase-oxidase substrate acting as a one-electron donor for enzyme compounds I, II and III. The one-electron peroxidatic oxidation of this serotonergic neurotoxin, responsible for the selective degeneration of central (5-hydroxytryptamine) neurons, is a fast process requiring measurement on the ms time scale. Attention is drawn to the biochemical and toxicological implications, because this fast reaction results in formation of known cell damaging species: free radicals, superoxide radicals and quinoidal products probably involved in the toxic action of 5,7-dihydroxytryptamine.