Cell responses to Injury II Flashcards
What can happen after reversible cell injury?
Pallor, Increased rugor and Increased weight
What occurs in the cytoplasm during reversible cell injury?
production of small clear vacuoles, distended/pinched off segments of ER and hyper-eosinophillia due to mitochondrial damage
What occurs in the nucleus during reversible cell injury?
Clumping of chromatin
What is the consequence of swelling of cells and organelles
Influx of water, loss of microvilli, detachment of ribosomes, mitochondrial swelling, clumping of nuclear chromatin, blebbing of plasma membrane
What causes necrosis?
it is caused by severe injury (ischaemia) e.g exposure to microbial toxins, burns, chemicals and leaking of proteases
or damage to cell contents
What is karyolysis?
the dissolution of the nucleus
What is karryorrhexis?
fragmentation of a nucleus
What is Pykenosis?
condensed nucleus
What is hyper-eosinophillia and its significance?
reduction in acidity of the cytoplasm, occurs during necrosis
What is coagulation necrosis?
Lesion to the blood vessel, there isnt as much inflammation as there is less blood
in kidneys it appears wedge-shaped
What is liquefactive necrosis?
infectious agents like bacteria produce toxins and send inflammatory signals
many ros are produced which are effective but cause damage to the tissue
What organ always has liquefactive necrosis?
The Brain
What is caseous necrosis?
In the centre of the organ, e.g the lungs
What is gangrenous necrosis?
damage to the blood vessel, e.g fungus that causes vasoconstriction
What is fat necrosis?
Caused by enzymes in the pancreas, and sabonfication mineralisation of necrotic tissue
What is fibrinoid necrosis?
Occurs in blood vessels and causes the vast majority of immune diseases
What is apoptosis?
Programmed cell death
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What are the steps of apoptosis?
Stress occurs
initiating membrane forms around (comes from the endoplasmic reticulum)
What is autophagy?
Cell eats its own contents as a survival mechanism
it reuses and degrades proteins to produce more material
What diseases can autophagy cause?
cancer, neurodegenerative diseases and infectious diseases
What does cell injury predispose to?
It predisposes to neoplasia, if cells dont have enough nutrients, neovascularisation can occur
What do intracellular accumulations look like histologically?
Enlarged cytoplasm with empty vacuoles
Nucleus is displaced to periphery
What is hyaline change?
glassy pink appearance in the histological sections stained with hematoxylin and eosin due to intracelluular accumulations
Name 4 things that can cause irrerable damage to cell components
- Denaturation of cell proteins
- Leakage of cellular content
- Damage of membranes
- Enzymatic digestion
