Chapter 1 Introduction to Pathophysiology; Cellular Responses to Stress, Injury, and Aging
Section 8 Outcomes of Cell Injury
Zoë Soon
When a cell is injured three possible outcomes exist.
- Recovery: The injury is reversible. The stressor is removed, the cell repairs itself, and normal function is restored.
- Apoptosis: The cell’s internal machinery determines that damage is too severe to repair, and the cell undergoes clean, programmed death.
- Unplanned cell death: The cell is overwhelmed and ruptures, causing inflammation and potential collateral damage to surrounding tissue.
- Necrosis: The premature death of a group of neighbouring cells or entire sections of tissue is referred to as necrosis.
Interesting Finding: Cell Death During Heart Attacks
Research into myocardial infarction (heart attack) has found that approximately 80% of cell death is apoptotic, and only 20% is necrotic. This means that the majority of hear cells sense low oxygen levels and deliberately undergo programmed death rather than bursting. This is clinically significant: apoptosis attracts fewer white blood cells, produces less ROS-mediated collateral damage, and actually speeds up healing relative to necrosis.