Amylase

Amylase is a digestive enzyme classified as a saccharidase (an enzyme that cleaves polysaccharides). It is mainly a constituent of pancreatic juice and saliva, needed for the breakdown of long-chain carbohydrates (such as starch) into smaller units.

Amylase is also synthesised in the fruit of plants during ripening, causing them to become sweeterer.

Alpha-amylase cleaves the α(1-4)glycosidic linkages of amylose to yield maltose molecules (disaccharides of α-glucose).

Increased plasma levels in humans are found in:

• Salivary trauma (including aneasthetic intubation).
• Mumps - due to pressure on the salivary glands.
• Pancreatitis - because of damage to the cells that produce amylase.
• Renal failure - due to reduced excretion.

The test for amylase is easy to perform and has been the main test for pancreatitis. Labs will usually measure either pancreatic amylase, or total amylase. If only pancreatic amylase is measured, an increase will not be noted with mumps or other salivary gland trauma.

Unfortunately, because of the small amount present, timing is critical when sampling blood for this measurement. Blood should preferably be taken soon after a bout of pancreatitis pain, otherwise it is excreted rapidly by the kidneys.