(LAB) Pancreatic Enzymes Flashcards
Lipase is also known as
Triacylglycerol Acylhydrolase
Lipase catalyzes TAG in the intestines into what
2-monoglyceride & fatty acids
Optimal Temp for Lipase Assay
40 C
Optimum pH for Lipase Assay
8.8
Lipase Assay Method:
Measures the liberated fatty acids by titration after a 24hr incubation
Classic Cherry-Crandall Method
Lipase Assay Method:
Based on the coupled reactions with enzymes
Colorimetric method
Substrate used for Classic Cherry-Crandall Method
Olive Oil
Pancreatic Enzymes that are stable in Serum
Lipase & Amylase
Lipase Assay Method:
Dispersed particles of hydrolyzed fats and the rate of clearing can be measured as an estimation of LPS activity
Turbidimetric Method
Enzymes with coupled reaction in the Colorimetric Method
Peroxidase
Glycerol Kinase
Modified substrate for Classic Cherry-Crandall Method
Triolein
What conditions do not interfere with Turbidimetric Method
Icterus
Lipemia
Hemolysis
Pancreatic Enzymes unstable in Serum
Lactate Dehydrogenase
In room temperature, how long will Lipase activity last before a loss
1 week
In 4 C, how long will Lipase activity last before a loss
at least 3 weeks
Why should Hemolysis be avoided in Lipase Assays
Hemoglobin inhibits serum in Lipase
Reference range of Lipase in Room Temperature
0-1.0 U/L
Reference range of Lipase at 37 C
< 38 U/L
Enzyme Commission Number of Lipase
E.C. 3.1.1.3
Enzyme Commission Number of Amylase
E.C. 3.2.1.1
Amylase is aka
1,4 - D - Glucan Glucanohydrolase
This Enzyme breaks down starch and glycogen to monosaccharides
Amylase
Activators of Amylase
Calcium & Chloride ions
Amylase found in Humans
Alpha Amylase
Amylase found in Plants
Beta Amylase
Amylase Assay Method:
AMS hydrolyzes starch, the Iodine is released and a decrease in the initial dark blue color intensity of the starch-iodine complex occurs.
Amyloclastic Method
In Amyloclastic Method, if there is a decrease in the Dark Blue Color Intensity, what does this mean for the AMS concentration?
Increase in AMS concentration
Amylase Assay Method:
The amount of reducing sugars is measured where the concentration is proportional to AMS Activity
Saccharogenic Method
Classic Reference method for Saccharogenic Method
Sumogyi Units
Amylase Assay Method:
As AMS hydrolyzes starch substrate, smaller dye substrate fragments are produced, and these are water soluble
Chromogenic Method
In the Chromogenic Method, if there is an increase in Color Intensity, what does this mean for the AMS Concentration?
Increase in AMS Concentration
Amylase Assay Method:
Have been used to determine AMS activity by a continuous-monitoring technique in which the change in absorbance of NAD+ at 340 nm is measured
Coupled-Enzymes
Difference between Coenzyme and Activator
Coenzyme - uses Organic substances
Activator - uses Inorganic substances
Amylase Assay Method:
Salivary and pancreatic amylase can be estimated by measuring total AMS in the presence and absence of lectin
Wheat Germ Lectin
This amylase assay method inhibits salivary amylase
Wheat Germ Lectin
Loss activity for Amylase in room temperature occurs when
1 week
Loss activity for Amylase at 4 C occurs when
2 - 6 months
Falsely elevates serum AMS levels
Morphine (Opiates)
Falsely lowers AMS activity
Anticoagulants:
Citrate
EDTA
Oxalate
Why is hemolysis not a problem in Amylase Assays
RBCS dont contains Amylase
Reference range of Amylase in Serum at 37 C
28 - 100 U/L
Reference range of Amylase in Urine
1 - 15 U/h
Enzyme Commission Number of Lactate Dehydrogenase
E.C. 1.1.1.27
This enzyme catalyzes the interconversion of lactic and pyruvic acid
Lactate Dehydrogenase
4 subunits of Lactate Dehydrogenase
LD-1 HHHH
LD-2 HHHM
LD-3 HHMM
LD-4 HMMM
LD-5 MMMM
Normal LD pattern
2 1 3 4 5
Flipped LD pattern
1 2 3 4 5
Causes of Flipped LD pattern
Myocardial Infarction
Anemia
Hemolysis
Substrate used for Electrophoresis in Lactate Dehydrogenase Assay
Alpha-hydroxybutyrate
Optimal pH of Forward Reaction in LD Electrophoresis
8.3 - 8.9
Optimal pH of Reverse Reaction in LD Electrophoresis
7.1 - 7.4
Lactate Dehydrogenase in Serum should be analyzed within how many hours?
48hrs
Most labile subunit of Lactate Dehydrogenase
LD-5 (MMMM)
LD isoenzyme analysis should be analyzed within how many hours?
24hrs
What anticoagulant does not interfere with AMS
Heparin
Ratio of anticoagulant in Blacktop (Differentiates it from Light Blue top)
1:4
Another name for the Forward Reaction in the Electrophoresis of Lactate Dehydrogenase
Wacker Method
Volume of Working Reagent
1000 uL
Volume of sample (LD , AMS)
10uL , 25 uL
Provided factor for Lactate Dehydrogenase estimation
16030
Provided factor of Amylase estimation
3178