1 Flashcards
name some causes of a change in plasma enzyme activity?
normally present in blood due to high turnover
necrosis or severe damage
neoplasia
increased synthesis of enzymes within cells
duct obstruction .
Name 5 important enzymes
Plasma cholinesterase Lactate Dehydrogenase Alanine transaminase Aspartate transaminase Creatine Kinase
Name the different combinations that isoenzymes contain for lactate dehydrogenase
M-Skeletal muscle cells
H-Cardiac muscle
What type of enzyme is creatine kinase
muscle enzymes helps maintain atp levels
where does CK predominate
Skeletal and cardiac muscle
What do dimeric B do and what does M do
B brain and M muscle
Name the three types of dimers and where do tey predominate
MM MB BB
MM skeletal muscle
mm (75%) MB(25%) cardiac muscle
BB Brain mainly
Name 2 diseases that CK is a marker on?
heart disease (MI) and muscle (muscular dystrophy )
Name the enzyme type from CK used to diagnose MI?
CK-MB
Where is AST predominant
all tissues but in heart liver and skeletal muscle
What can ALT be used to measure
primarly liver ,kidney, skeletal
Where is alkaline phosphatase
liver, bone and placenta significant
what is gamma glutamyl tranferase
Mainly in kidney, liver, biliary tract, pancreas
important in diagnosis of liver disease
induced by alcohol and other drugs
Amylase sign
-Amylase
present in pancreas and salivary glands (different isoenzymes)
used mainly to diagnose acute intra-abdominal conditions eg acute pancreatitis
Cholinesterase
Cholinesterase
liver form found in plasma
acetylcholinesterase found in cholinergic nerve endings, not plasma
Low plasma ChE used for diagnosis of scoline apnoea and organophosphorus poisoning
what is myocardial infarction
Myocardial infarction resulting from coronary thrombosis
Area of heart becomes severely ischaemic; since heart is a totally oxidative tissue
Resulting lack of oxygen leads to severe tissue damage in ischaemic area
Name some enzyme and protein markers for MI
CK inc. CK-MB
CK-MB more sensitive & specific for MI than total
CK-MB mass now most common (ie immunoassay)
AST
LD (esp H4)
other proteins:
myoglobin - rapid release, but not cardiac specific
cTroponin I - highly cardiac specific
cTroponin T - very cardiac specific
What is the initial lag phase
initial lag-phase 3 h; enzymes/proteins rise to peak in 18-36h -
when do enzyme peak when thrombolytic
enzymes peak @ 10-18h
name enzyme markers for liver disease
Liver disease: ALT & AST raised in heptatocellular damage; GGT and ALP in cholestatic disease
