(LEC) LDH & CK

Question 1

EC of Lactate Dehydrogenase

Answer 1

EC 1.1.1.27

Question 2

LDH is a _____ containing enzyme

Answer 2

Zinc

Question 3

Catalyzed the interconversion of Lactic Acid and Pyruvic Acid

Answer 3

Lactate Dehydrogenase

Question 4

Coenzyme used by LDH

Answer 4

NAD+

Question 5

Molecular weight of LDH

Answer 5

128 kDa

Question 6

LDH has 4 subunits, hence LDH is termed as

Answer 6

Tetramer

Question 7

LDH isoenzyme that migrates the fastest towards the anode

Answer 7

LD-1

Question 8

LDH isoenzyme that migrates the slowest towards the anode

Answer 8

LD-5

Question 9

The major fraction of LDH isoenzyme in healthy individuals

Answer 9

LD-2

Question 10

Reference range for LDH

Answer 10

125 - 220 U/L

Question 11

LDH Isoenzyme that predominates in the Serum

Answer 11

LD-2

Question 12

LDH Isoenzyme that predominates in the Lungs

Answer 12

LD-3

Question 13

LDH Isoenzyme that predominates in the Skeletal Muscle

Answer 13

LD-5

Question 14

LDH Isoenzyme that predominates in the Liver

Answer 14

LD-5

Question 15

Clinical Correlation for Highest Level of Total LDH

Answer 15

Pernicious Anemia
Hemolytic Disorders

Question 16

LDH isoenzyme from the Heart & RBCs

Answer 16

LD-1 (HHHH) & LD-2 (HHHM)

Question 17

LDH isoenzyme from the Lungs, Lymphocytes, Spleen, and Pancreas

Answer 17

LD-3 (HHMM)

Question 18

LDH isoenzyme from the Liver

Answer 18

LD-4 (HMMM)

Question 19

LDH isoenzyme from the Skeletal Muscle

Answer 19

LD-5 (MMMM)

Question 20

Causes LD Flipped Pattern

Answer 20

Myocardial Infarction & Intravascular Hemolysis

Question 21

LDH Isoenzyme elevated in Liver Damage/Intrahepatic Disorders

Answer 21

LD-4

Question 22

LDH Isoenzyme elevated in Skeletal Muscle Damage/Muscle Dystrophy

Answer 22

LD-5

Question 23

Isomorphic pattern when Total LDH is increased and the relative amount of each isoenzyme is roughly the same

Answer 23

Tombstone Pattern

Question 24

This LDH Isoenzyme migrates cathodic to LD-5 and is an alcohol dehydrogenase, and signifies grave prognosis and impeding death

Answer 24

LD-6

Question 25

Optimal pH for Forward Reaction in LDH Assay

Answer 25

pH 8.3 - 8.9

Question 26

Optimal pH for Reverse Reaction in LDH Assay

Answer 26

pH 7.1 - 7.4

Question 27

Other name for Creatine Kinase

Answer 27

Creatine Phosphokinase

Question 28

EC of Creatine Kinase

Answer 28

EC 2.7.3.2

Question 29

Molecular weight of CK

Answer 29

82 kDa

Question 30

Associated with ATP regeneration in contractile or transport systems

Answer 30

Creatine Kinase

Question 31

3 CK Isoenzymes

Answer 31

CK-BB (brain)
CK-MB (cardiac)
CK-MM (skeletal & cardiac)

Question 32

Reference range of CK

Answer 32

46 -171 U/L (Males)
34 - 145 U/L (Females)

CK-MB <= 5% of Total CK

Question 33

In Electrophoresis, which CK Isoenzyme migrates fastest towards anode

Answer 33

CK-BB

Question 34

In Electrophoresis, which CK Isoenzyme migrates slowest towards anode

Answer 34

CK-MM

Question 35

Half-Life of CK-BB

Answer 35

1 - 5 hrs

Question 36

Molecular size of CK-BB

Answer 36

80 kDa

Question 37

20% of all CK-MB comes from?

Answer 37

Cardiac Tissue

Question 38

These are more sensitive and more specific than CK-MB, may elevate in the absence of CK-MB elevation

Answer 38

Troponins

Question 39

Major CK Isoenzyme in the sera of healthy people

Answer 39

CK-MM

Question 40

CK Isoenzyme band that is 0.8 - 1.6% of Total CK in the Serun

Answer 40

Macro-CK

Question 41

CK Isoenzyme band that has a MW of 350 kDa

Answer 41

Mitochondrial-CK

Question 42

Is an enzyme released from the erythrocytes in hemolyzed samples and may appear cathodal or prior to CK-MM

Answer 42

Adenylate kinase

Question 43

in Immunoinhibition Method to determine CK-MB, what is used to inhibit M activity

Answer 43

anti-M

Question 44

in Radio Immunoassay to detect CK-MB, rather than activity, what is measured?

Answer 44

Enzyme Concentration