Peroxynitrite is demonstrated to cause apoptosis in freshly harvested
rat thymocytes suspended in phosphate buffer, as shown by the typical
ladder pattern of DNA fragmentation. This evidence suggests a new func
tion for peroxynitrite, already known to be a strong oxidant. Peroxyni
trite can nick DNA, oxidize cellular thiols and initiate the apoptotic
process responsible for genomic degradation. (C) 1995 Academic Press,
Inc.