Mechanisms of Irreversibility in Cell Injury

Currently, the precise biochemical events initiating irreversible cell injury are unknown. At what stage did the cell actually die What is the critical biochemical event responsible for the point of no return There is no universally accepted biochemical explanation for the transition from reversible injury to cell death. The duration of hypoxia necessary to induce irreversible cell injury varies according to cell type and its nutritional and hormonal status  

The inability to reverse mitochondrial dysfunction upon reperfusion, causing ATP depletion. 

ATP depletion is certainly an important player in ischemic damage. But, drastic lowering of cellular ATP levels by the use of metabolic inhibitors has shown that this single event does not induce irreversible cell injury. Likewise, as discussed above, activation and release of lysosomal enzymes, subsequent to decreased intracellular 

TABLE 16.1. Organ-Specific Leakage Enzymes Detectable in Scriini/l lasina 

Liver ALT Alanine aminotransferase is fairly liver-specific in some species. 

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