140 - Practical Use of Liver Enzymes in Diagnosing Liver Disease Flashcards
Examples of liver-secreted blood proteins
Clotting factors
Breakdown of what marks cell death?
Cytoskeleton
Mild appearance of damaged cells
Cytoskeleton is damaged.
Blebs form from surface of cell, released into the blood
Features of apoptosis 1 2 3 4
- Nuclear degeneration
- Cytoskeletal degeneration
- Membrane Blebbing
- Shrinking
Things to consider with enzymes detected in the blood
1
2
3
1) Which cell did they escape from?
2) How did they get into the blood?
3) How will they be removed from the blood?
Cytoplasmic liver enzymes
ALT, AST, LD
Membrane liver enzymes
ALP, GGT
Organelle liver enzymes
Mitochondrial AST, lysosomal Superoxide dismutase
Things released from necrotic liver cells
ASL, AST, LD
Things released in biliary disease
AST, GGT
Things released with inducing drugs
GGT, ALP
ALT
Converts pyruvate to lactate (Cori cycle, anaerobic use of glucose)
Cori cycle
Occurs mainly in liver and muscle.
Anaerobic use of glucose
AST
Converts oxo-glutarate and aspartate to oxaloacetic acid and glutamate in the malate shuffle.
Where is ALT found?
Mostly in liver.
Slightly less in muscle and kidney.
More specific to liver than AST is.
Where is AST found?
In cytosol and in mitochondria.
Liver, muscle, blood cells.
Less specific to the liver than ALT is.
ALT half life
36 hours
AST half life
18 hours