Contracture development in anoxia: the importance of asynchrony.

Several studies have reported a linear correlation between ATP levels, measured on isolated adult heart cells exposed to anoxia, and cellular configuration. The case is presented here for the viewpoint that these results can best be explained by an asynchronous decline in cellular ATP levels. By asynchrony we mean that an individual cell maintains a constant high level of ATP for a lag period until some point when, over a short period of time, the ATP level suddenly drops to near zero; the time spread of the decline in total measured ATP then arises from a spread in lag periods amongst the cells. By contrast, the synchronous view assumes that the time spread of the decline in total measured ATP reflects the simultaneous slow decline of ATP levels within each cell. These viewpoints have important consequences for elucidating the etiology of cell death.