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Clinical Chemistry, Vol 39, 746-756, Copyright © 1993 by American Association for Clinical Chemistry
NW Tietz and DF Shuey
Department of Pathology and Laboratory Medicine, University of Kentucky Medical Center, Lexington 40536.
Lipase is a glycoprotein with 420-449 amino acid residues and a M(r) of 46,000-56,000 for pancreatic lipase and 32,000-39,000 for serum lipase. Lipase is present in the pancreas, intestines, and a variety of other tissues. The concentration gradient between pancreatic tissue and serum lipase is approximately 20,000-fold. Serine, as part of an Asp-His-Ser triad, is the nucleophilic residue essential for catalysis. Lipase differs from other esterases by the presence of a hydrophobic recognition site. The optimal pH is between 7.5 and 10.0, depending on the reaction condition; the pI for the various forms of the enzyme has been reported as 5.80 and 5.85; 6.4, 6.8, and 7.0; and 7.4 for a purified fraction. Several authors report the presence of two molecular forms in the pancreas and three electrophoretic bands with lipolytic activity. In normal serum two bands have been observed; in pancreatitis as many as four bands have been seen. Lipolytic activity may not always be due to lipase. Assays specific for lipase require a triglyceride as substrate as well as the presence of colipase (a water-soluble and heat- stable protein, essential for lipase action), a secondary bile salt, and Ca2+. The clinical sensitivity of all modern assays is high because of selection of a low decision limit; the clinical specificity varies greatly but can be improved by increasing the cutoff point. Lipase determinations in pancreatitis are superior to amylase determinations. The reasons for the great variability of reports regarding the clinical utility of lipase are discussed, and the clinical utility of lipase determinations is summarized.
The following articles in journals at HighWire Press have cited this article:
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  M. Cloutier, D. Gingras, and M. Bendayan Internalization and Transcytosis of Pancreatic Enzymes by the Intestinal Mucosa J. Histochem. Cytochem., July 1, 2006; 54(7): 781 - 794. [Abstract] [Full Text] [PDF]
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 W R Matull, S P Pereira, and J W O'Donohue Biochemical markers of acute pancreatitis. J. Clin. Pathol., April 1, 2006; 59(4): 340 - 344. [Abstract] [Full Text] [PDF]
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 A. A. Rizvi Serum Amylase and Lipase in Diabetic Ketoacidosis Diabetes Care, November 1, 2003; 26(11): 3193 - 3194. [Full Text] [PDF]
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 G. Cattozzo, C. Franzini, and G. Melzi d'Eril Commutability of Calibration and Control Materials for Serum Lipase Clin. Chem., December 1, 2001; 47(12): 2108 - 2113. [Abstract] [Full Text] [PDF]
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Y. E. Taes, H. Louagie, J.-P. Yvergneaux, M. L. De Buyzere, H. De Puydt, J. R. Delanghe, and J. A. Lott Prolonged Hyperlipasemia Attributable to a Novel Type of Macrolipase Clin. Chem., December 1, 2000; 46(12): 2008 - 2013. [Abstract] [Full Text] [PDF]
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M. Munoz-Perez, D. Sarrion-Pelous, J. Jimenez-Jimenez, P. Martinez-Montiel, and M. Gallego-Valdes Chronic Increased Serum Lipase in a Patient with Suspected Pancreatic Adenocarcinoma Clin. Chem., January 1, 1997; 43(1): 191 - 193. [Full Text]
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