Cellular Pathology, TBP Flashcards
4 basic types of cellular adaptations
1) Hyperplasia
2) Hypertrophy
3) Atrophy
4) Metaplasia
Increase in number of cells
Hyperplasia
Permanent cells (do not undergo hyperplasia) (3)
1) Cardiac cells
2) Neurons
3) Skeletal muscle cells
Increase in size of cell
Hypertrophy
T/F: Hyperplasia and hypertrophy can be distinguished grossly
F
Physiologic vs pathologic, hyperplasia vs hypertrophy: Increase in size of breast during pregnancy
Physiologic hyperplasia
Physiologic vs pathologic, hyperplasia vs hypertrophy: Adrenal enlargement due to pituitary adenoma
Pathologic hyperplasia
Physiologic vs pathologic, hyperplasia vs hypertrophy: Skeletal muscle enlargement during exercise
Physiologic hypertrophy
Physiologic vs pathologic, hyperplasia vs hypertrophy: LVH
Pathologic hypertrophy
Physiologic vs pathologic, hyperplasia vs hypertrophy: Increase in thickness of endometrium during menstrual cycle
Physiologic hyperplasia
Physiologic vs pathologic, hyperplasia vs hypertrophy: Endometrial proliferation due to prolonged estrogen stimulus
Pathologic hyperplasia
Physiologic vs pathologic, hyperplasia vs hypertrophy: Liver growth after partial resection
Physiologic hyperplasia
Mechanisms by which hyperplasia and hypertrophy can occur (2)
1) Up regulation or down regulation of receptors
2) Induction of new protein synthesis
New proteins induced (3)
1) Transcription factors
2) Contractile proteins
3) Embryonic proteins
Decrease in size of cell that has once been of normal size
Atrophy
Physiologic vs pathologic atrophy: Decrease in size of uterus after pregnancy
Physiologic
Stimuli for pathologic atrophy (7)
1) Loss of blood supply
2) Loss of nerve supply
3) Loss of endocrine stimulation
4) Disuse
5) Mechanical compression
6) Decreased workload
7) Aging
Organ that is small in size and was never normal in size
Hypoplasia
Eccentric vs concentric cardiac hypertrophy: Pressure overload
Concentric
Eccentric vs concentric cardiac hypertrophy: Volume overload
Eccentric
Change in epithelium from one type to another
Metaplasia
Metaplasia: Barrett esophagus
Glandular metaplasia
Metaplasia: Smoker’s lung
Squamous metaplasia
Occurs when cells cannot adapt to new environment
Cell injury
2 common sources of cellular injury
1) Ischemia
2) Hypoxia
Ischemia vs hypoxia: Much more damaging
Ischemia
T/F Cellular injury always results in cell death
F
4 cellular systems especially vulnerable to cellular injury
1) DNA
2) Cell membranes
3) Protein generation
4) ATP production
Mechanisms of cellular injury (4)
1) Hypoxia
2) Generation of oxygen-derived free radicals
3) Chemical injury
4) Increased mitochondrial cytosolic calcium
Mechanisms of cellular injury: Decrease in O2 results in decreased
ATP production
Mechanisms of cellular injury: ATP is required by (2)
1) Na/K ATPase pump
2) Ca pump
Mechanisms of cellular injury: Entry of calcium into cells cause
Activation of endonucleases, proteases, phospholipases, and DNAses that damage cells
Mechanisms of cellular injury: Decrease in O2 results in increased
Anaerobic respiration resulting in accumulation of lactic acid, decreasing cellular pH
Mechanisms of cellular injury: Decrease in intracellular pH results in
Disaggregation of ribosomes from RER
Mechanisms of cellular injury: A molecule with an unpaired electron in the outer orbit
Free radical
Mechanisms of cellular injury: Another term for free radical
ROS
Mechanisms of cellular injury: Normal physiologic reactions that generate free radicals
Redox reactions
Mechanisms of cellular injury: Damage by free radicals (3)
1) Lipid peroxidation
2) DNA fragmentation
3) Protein cross-linking
Mechanisms of cellular injury: Methods to prevent formation of ROS (4)
1) Catalase
2) Superoxide dismutase
3) Glutathione
4) Vitamin ACE
Mechanisms of cellular injury: Action of catalase
Degrades hydrogen peroxide
Mechanisms of cellular injury: Action of superoxide dismutase
Converts superoxide to hydrogen peroxide
Mechanisms of cellular injury: Action of glutathione
Catalyzes breakdown of hydroxyl radicals
Mechanisms of cellular injury: Toxic metabolite of ethylene glycol (antifreeze)
Oxalic acid
Mechanisms of cellular injury: Toxic metabolite that directly inactivates cytochrome oxidase, impairing formation of ATP
Cyanide
Mechanisms of cellular injury: Increased mitochondrial cytosolic calcium leads to (3)
1) Lipid peroxidation
2) Formation of mitochondrial permeability transition
3) Release of cytochrome c
Mechanisms of cellular injury: Mitchondrial permeability transition
Nonselective pore that dissipates proton gradient
Mechanisms of cellular injury: Action of cytochrome c
Activates apoptosis
Light microscopic findings of reversible cellular injury
1) Cellular swelling
2) Fatty change
Ligt microscopic findings of irreversible cellular injury
1) Nuclear karyolysis
2) Nuclear pyknosis
3) Nuclear karyorrhexis
2 most important factors determining irreversible cell damage
1) Membrane distrubances
2) Inability to reverse mitochondrial dysfunction
Loss of nuclear basophilia
Karyolysis
Shrinkage of nucleus
Pyknosis