BIOM20001 Lecture Notes - Lecture 58: Phospholipid, Homeostasis, Anaerobic Glycolysis
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Cellular swelling
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Fatty change (lipid accumulation in vacuoles in cytoplasm)
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Light microscope
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Plasma membrane blebbing
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ER and mitochondrial changes
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Nuclear alterations
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Ultrastructural
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Occurs when mitochondrial dysfunction can't be reversed
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And when membrane lose structural integrity (PM and internal membranes)
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Contents leak into cell
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Nuclear and cytoplasmic components degraded
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Lysosomal membranes
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Loss of osmotic balance
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Cellular contents leak into extracellular space (inflammation)
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Plasma membrane
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Mitochondrial membrane
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Morphological features of irreversible injury
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e.g. pathology: cellular swelling -> pathogenesis: ATP dependent ion channels don't function.
This messes up osmotic balance causing swelling
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Complex, interconnected and tightly interwoven
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Mitochondria: lower ATP, higher ROS
Result in abnormalities of essential cellular components
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Mechanisms of cell injury: pathology to pathogenesis
MCB Page 6
Mitochondria: lower ATP, higher ROS
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Calcium homeostasis
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Plasma membrane
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DNA and proteins
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MCB Page 7
Document Summary
Fatty change (lipid accumulation in vacuoles in cytoplasm) And when membrane lose structural integrity (pm and internal membranes) Mechanisms of cell injury: pathology to pathogenesis e. g. pathology: cellular swelling -> pathogenesis: atp dependent ion channels don"t function. Get influx of na+, ca2+ and water and an efflux of k+. Ca2+ also affects cytoskeleton - cell loses scaffolding. Produce lactic acid which lowers ph which causes clumping of chromatin (observable under light microscope ). Also detaches ribosomes from er with reduces protein synthesis. Ultimately this causes necrosis if membrane of lysosome is damaged or mt can"t recover. Damage due to oxidative stress (ros) -> produces less atp. Mitochondrial permeability transition: pores in membrane of mt. Mitochondrial proteins (e. g. cytochrome c) can be released into cytoplasm due to some injury. Intracellularly it is sequestered in mt and er but after na+/k+ pump fails, we get an influx of ca2+ into cell - increase cytosolic levels of calcium.
