Amylase, Pancreatic, Serum
Method Description Describes how the test is performed and provides a method-specific reference
After the inhibition of salivary amylase with a combination of 2 monoclonal antibodies, pancreatic alpha-amylase activity is assayed by a coupled kinetic colorimetric procedure which gives rise to 415 nm absorption proportional to the paranitrophenol released by the action of alpha-amylase and alpha-glucosidase.
In this procedure, the first incubation step results in the inhibition of human salivary alpha-amylase by 2 monoclonal antibodies which do not affect pancreatic alpha-amylase. After a second incubation with the substrate (G7)-p-nitrophenyl (G1)-alpha-D-maltohepatoside, the activity of pancreatic alpha-amylase is measured. The alpha-amylase cleaves the substrate into fragments G2, G3, and G4. Further fragment hydrolysis by alpha-glucosidase yields p-nitrophenol and glucose. Enzyme activity is determined by the rate of increase of absorbance at 415 nm. Chromophore production is equimolar.
The simplified reaction is as follows:
5 ET-G7PNP + 5 H20 -------> 2 ET-G5 + 2 G2PNP + 2 ET-G4
+ 2-G3PNP + ET-G3 + G4 PNP
2 G2PNP + 2 G3PNP + 14 H20 --------->5 PNP + 14G
Abbreviations: ET = ethylidene
G = glucose
PNP = p-nitrophenol
(Tietz NW, Burlina A, Gerhardt W, et al: Multicenter evaluation of a specific pancreatic isoamylase assay based on a double monoclonal-antibody technique, Clin Chem 1988;34:2096-2102)
Day(s) and Time(s) Test Performed Outlines the days and times the test is performed. This field reflects the day and time the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time required before the test is performed. Some tests are listed as continuously performed, which means assays are performed several times during the day.
Monday through Friday
Analytic Time Defines the amount of time it takes the laboratory to setup and perform the test. This is defined in number of days. The shortest interval of time expressed is "same day/1 day," which means the results may be available the same day that the sample is received in the testing laboratory. One day means results are available 1 day after the sample is received in the laboratory.
1 day (not reported on Saturday or Sunday)
Maximum Laboratory Time Defines the maximum time from specimen receipt at Mayo Medical Laboratories until the release of the test result
Specimen Retention Time Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded
Performing Laboratory Location The location of the laboratory that performs the test