Cell Injury Flashcards
Cell injury
Ischemia
Infection
Immune reaction
Chemical factors
Physical factors
Nutritional factors
Psychosocial
Age
Ischemia
Blood flow is insufficient to maintain homeostasis and metabolic function
Like hypoxia or anoxia
Loss of aerobic metabolism, reduction in ATP synthesis, accumulation of ions in fluid intracellularly, cells swell, and their function is compromised
Could be a circulatory issue, metabolism issue, respiratory inadequate transport, or just inadequate transport
Infection and immune reaction
Bacterial infections
Viral infections
Immune reactions
Bacterial infections
Bacteria encounter second line of defense an inflammatory response
Endotoxins induce the synthesis of systemic manifestations of sepsis
Exotoxins damage, host cells, or disrupt normal cellular processes
Viral infections
Direct, cytopathic effect RNA viruses- viral replication, or disrupt integrity of nucleus in plasma membrane
Indirect cytopathic effect DNA viruses- foreign viral proteins, is inserted in cell membrane, and is now recognized by the immune system to be destroyed
Immune reactions
Hypersensitivities or auto immune disorders
Chemical factors
Include carbon monoxide, ammonia, heavy metals like mercury and aluminum, alkylating agents in pharmaceutical drugs, and free radicals
Carbon monoxide and ammonia, most injuries and death
Free radical formation
Unstable byproduct of oxidation that destroys cell membranes associated with cancer, atherosclerosis, Alzheimer’s, disease and Parkinson’s disease
Antioxidants
neutralizes the free radicals
Examples include vitamin C, E and Beta carotene
Nitric oxide is a beneficial, free radical that needs vasodilation and decreases atherosclerosis
Physical factors
Physical
Blunt, trauma, temperature, radiation, and electricity
Mechanical
Tissue tolerance - age, utilization
Load- compression fraction torsion where sheer force is based on property of tissue
Magnitude- high load repeated bouts of moderate load
Nutritional factors
Vitamin and mineral deficiencies
Vitamin B 12 deficiency - neuropathy
Calcium deficiency - decreased bone quality
Protein malnutrition - edema, weight loss, and diminished functional capacity
Psychosocial factors
Fear, tension, anxiety, depression, isolation
Cellular aging
Progressive decline in homeostatic balance, which leads to pathology
Free radical theory of aging causes DNA damage
Cell injury reversible versus irreversible
Reversible- able to adapt, alterations in cellular mechanisms
Irreversible - unable to adapt, cell death, necrosis
Reversible injury
Swelling of the cell, endoplasmic reticulum, mitochondria and cell becomes acidic
