... ETA -A in the presence of ATP, with concomitant generation of ETA and ETA -A fragments. Incubation in the absence of ATP revealed a small amount of degrada-tion for intact ETA, whereas no degradation ... postinjection)ABFig. 1. Kinetics of appearance of ETA in hepatic plasma membranes and endosomes after toxin administration. Rat hepatic plasma mem-brane (A) and endosomal fractions (B) were isolated at the ... infection, as assessed by the mitochondrial release of cytochrome c, caspase-9 and caspase-3 activa-tion, and DNA fragmentation. In an in vitro assay, intact ETA inducedADP-ribosylation of EF-2 and...