Serum
Aspartate
amino
Transferase
(AST)
Omeed Akbar Ali
Biochemistry Lab.
1
As
partate
T
ransaminase (
AST
)
Aspartate transaminase (
AST
) also called serum glutamic oxaloacetic transaminase (
SGOT
) (EC
2.6.1.1).
•
AST was defined as a biochemical marker for the diagnosis of acute myocardial infarction in 1954.
▪ However the use of AST for such a diagnosis is now redundant and has been superseded by the
cardiac Troponins
.
•
AST (SGOT) is commonly measured clinically as a part of diagnostic
liver function tests
, to
determine liver health.
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AST Functions
3
Two isoenzymes are present in humans.
GOT1
, the cytosolic isoenzyme derives mainly from
red blood cells
and
heart
.
GOT2
, the mitochondrial isoenzyme is predominantly present in
liver
.
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Glutamic-Oxaloacetic Transaminase (GOT) occurs in large concentrations in the
heart
and
liver
with moderate amounts in
skeletal muscle
,
kidneys
, and
pancreas
.
GOT levels can be used to diagnose myocardial infarction within
10-48 hours
.
Peak at 24-48
hours.
Other conditions with elevated GOT include arrhythmias and severe angina of the heart,
and liver damage.
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Cardiac Diagnostic
Cardiac Troponin T and I
Levels increase ↑
3-12 hours
from onset of chest pain
Peak at 24-48 hours.
Return to
normal levels in 5-14 days
Cardiac Enzymes
1-Creatine Kinase
3 types of CK, CK-MB is variant used in diagnosis of acute MI.
Levels begin to ↑
3-12hrs
after
event,
peak within 24hrs
and
return to
normal after hrs
.
2-Lactate Dehydrogenase
In myocardial infarction, LDH increases ↑
3-12 hours
after the onset of
pain
Peaks at 48-60 hours
and remain elevated for
10-14 days
.
6
3-AST
levels can be used to diagnose myocardial infarction within ↑
10-48 hours.
Peak at 24-48 hours
Thanks For
Listening …
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