Mechanisms of Cell Injury

May 27, 2012 | By | Reply More

Mechanisms of Cell Injury

Depletion of ATP
Mitochondrial Damage
Influx of Intracellular Calcium and Loss of Calcium Homeostasis
Accumulation of Oxygen-Derived free radical (Oxidative stress)
Defects in Membrane Permeability
Depletion of ATP

Causes

  •    Hypoxia, Ischemia
  •    Chemical Injury

Mitochondrial Damage

Causes

  •     Hypoxia, Toxins
  •     Cytosolic Ca2+
  •     Oxidative stress
  •     Lipid breakdown product
Mitochondrial permeability transition of inner membrane (formation of high-conductance channel)

Mitochondrial Oxidative Phosphorylation ↓

ATP production ↓

Leakage of Cytochrome c into cytosol
Influx of Intracellular Calcium and Loss of Calcium Homeostasis
Accumulation of Oxygen-Derived Free  Radicals (Oxidative Stress)
The Oxidation-Reduction reaction (normal metabolic processes)

-superoxide anion (O2-)

-hydrogen peroxide (H2O2)

-hydroxyl ion (OH )

Absorption of radiant energy (ultraviolet light: UV, X-ray)
Transition Metals – iron, copper
Defects in Membrane Permeability

Mechanism of Membrane damage in Cell Injury

Mitochondrial Dysfunction

-Decreased phospholipid synthesis

-Phospholipase activation

Loss of Membrane phospholipid

Mechanism of Membrane damage in Cell Injury

Cytoskeletal Abnormality

Reactive Oxygen species

Lipid breakdown products

(detergen effect on membrane)

,,,,,,,,……………..

 

Tags:

Category: Pathology

WARNING: Any unauthorised use or reproduction of  www.neuronarc.com content for commercial or any purposes is strictly prohibited and constitutes copyright infringement liable to legal action.