Amylase pancreatic, assay

L16. Lott, J. A., and Lu, C. J., Lipase isoforms and amylase isoenzymes Assays and application in the diagnosis of acute pancreatitis. Clin. Chem. 57, 66-68 (1991). 

E682 Tetrault, G. (1990). Serum lipase assayed on Ektachem 700 is not specific for pancreatitis in patients with elevated amylase or lipase. Clin. Chem. 36, 1123, Abstr. 800. 

Junge W, Wortmann W, Wilke B, Waldenstrom J, Kurrle-Weittenluller A, Fioke J, Klein G. Development and evaluation of assays for the determination of total and pancreatic amylase at 37°C according to the principle recommended by the IFCC. Clin Biochem 2001 34 607-15. 

Rauscher E> Gerber M. Pancreatic a-amylase assay employing the synergism of two monoclonal antibodies. Clin Chim Acta 1989 183 41-4. 

Although several enzyme measurements are available for assessing gastrointestinal function, these assays are not frequently used amylase and/or lipase are perhaps measured more often than other enzymes in order to evaluate pancreatic toxicity. Some enzyme measurements require the invasive collection of gastric, pancreatic, and intestinal fluids, or tissues and therefore are not suitable for many toxicological studies. 

Total plasma amylase can be measured using chromogenic methods with one of several nitrophenyl-linked synthetic substrates, although not all substrates are suitable for use with samples from laboratory animals (Braun et al. 1990 Medaille and Breind-Marchal 2004), and the methods used for human samples may need to be adjusted by reducing the reaction sample volumes because the levels of plasma amylase are much higher in laboratory animals. Assays using monoclonal antibodies are now available to measure pancreatic (P) lipase, and these are suitable for use with some laboratory animals. 

Severe hypertriglyceridaemia may be associated with recurrent attacks of abdominal pain and sometimes pancreatitis. This lipid abnormality may interfere with the assay for amylase in some laboratories. Hepatosplenomegaly due to accumulation of lipid-laden macrophages may occur. Rarely there may be memory disturbances and lack of... 

Background Serum biomarkers for exocrine pancreatic injury in humans and preclinical species traditionally include amylase and lipase. In terms of assay methodology, serum amylase and lipase use an activity-based endpoint, which utilizes the substrate (e.g., diacylglycerol is the lipolytic substrate for serum lipase) to detect the serum activity levels. The assays have been used for over a decade in diagnostic... 

Because these enzymes are not specific to the pancreas and are rapidly cleared by the kidneys, serum amylase and lipase are now considered to be of very little value in the diagnosis of DIAP. However, in suspected cases of pancreatic injury where elevations in amylase or lipase do occur, the lack of tissue specificity can be addressed by the use of assays specific for the pancreatic form of each enzyme (i.e., pancreatic (or p-)amylase and p-lipase, respectively). 

A new assay for pancreatic and salivary amylases in sera requires neither electrophoresis nor chromatography. It is based on inhibition of the salivary amylases with a protein from wheat, which allows the pancreatic amylases to be estimated separately. The assay was used to measure the levels of pancreatic and salivary amylases in the sera of healthy men and women and individuals with pancreatitis, mumps, and other diseases. 

Comparisons of the products resulting from the action of porcine pancreatic a-amylase on Amylose-Cibacron Blue 3G-A (a dyed amylose) and amylose indicated that enzymic hydrolysis of the dyed amylose is modified. These observations were discussed with reference to the use of Amylose-Cibacron Blue 3G-A for the assay of a-amylase in clinical work. 

A solid-state radioimmunoassay has been developed for the detection and measurement of porcine pancreatic a-amylase. A double-antibody radioimmunoassay that is able to determine and detect small amounts of pancreatic amylase, even in the presence of amylase isoenzymes, has been reported. The assay was used to ascertain the effects of pancreatectomy on the levels of amylase in porcine tissues, and it was concluded that the pancreas contributes significantly to the levels of circulating amylase. 

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