CC2 LAB: CREATININE KINASE, ALT, AST Flashcards
ppt based
associated with atp regeneration in contractile or transport system
creatinine kinase
ck is predominant in
muscle cells
how many kDa in ck
82
separation of atypical bands
detection of ak
electrophoresis (reference method)
good with technique, may be more sensitive and precise
ion-exchange chromatography
measure concentration rather than activity
may detect inactive ck-mb
radioimmunoassay
- anti-M inhibits M activity
- CK activity is measure before and after inhibition
- residual activity is multiplied by 2 to account for MB
(50% inhibited) - disadvantage: detects BB activity; though small amount,
may cause false MB activity; also, atypical forms are not
inhibited
immunoinhibition
A in Coupled-enzyme method
340 nm
forward reaction in ck
Tanzer-Gilvarg
- reverse reaction in ck
- most common
- 2 – 6x faster than forward
- less interference
Oliver Rosalki
Tanzer-Gilvarg Method pH
pH 9.0
Oliver-Rosalki Method pH
pH 6.8
inactivated because of oxidation of sulfhydryl groups
CK activity unstable
T/F: Hemolyzed samples falsely elevate CK activity
T
ratio of ck
1:4
working reagent (microliter) ck & ck-mb
1000uL
sample (microliter) ck & ck-mb
40uL
Transfer of an amino group
between aspartate and alpha-
keto acids to form oxaloacetate and glutamate
Aspartate Aminotransferase
coenzyme of ast
Pyridoxal phosphate
former name of ast
serum glutamic-oxaloacetic
transaminase
Consists of a coupled enzymatic reaction using Lactate Dehydrogenase as the
indicator enzyme
alt
Transfer of an amino group
between alanine and alpha-
keto acids to form glutamate
and pyruvate
Alanine Aminotransferase
coenzyme of alt
Pyridoxal phosphate
former name of alt
serum glutamic-pyruvic
transaminase
Catalyzes the reduction of pyruvate to lactate with simultaneously oxidation of NADH
alt
optimal pH of alt
7.3 – 7.8
Relatively unaffected by hemolysis
alt
sample of ast in microliter
100
coupled enzymatic reaction
▪ AST and malate dehydrogenase (MD) as the
indicator reaction
▪ change in absorbance at 340 nm as NADH is
oxidized to NAD+
Karmen Method
Optimal pH of ast
7.3 – 7.8
reaction with … couples color reagent with keto acid product
dinitrophenylhydrazine
Hemolysis should be avoided
ast
reaction with … couples the
salt with the keto acid product and forms a color
diazonium salts
