Distribution of amylase in the gastrointestinal tract of the rat

¹ Department of Biochemistry, University of Louisville School of Medicine, Louisville, Kentucky

Amylase levels of the serum, stomach, duodenum, jejunum, cecum and colon in rats were determined by Van Loon's amyloclastic method. The rats used were in several categories: normal, fasted 7 days, with liver damaged by N-nitrosodimethylamine, pancreatectomized and both salivarectomized and pancreatectomized. Amylase was found throughout the gastrointestinal tract in all rats, being highest in the normals. In the normal rats, the amylase level of the jejunum was slightly higher than that of the duodenum. The same is true for the pancreatectomized and pancreatectomized-salivarectomized rats but in the fasted rats and those with liver damage, the reverse is true. Despite removal of the known sources of amylase, the enzyme persisted in the gastrointestinal tract of salivarectomized-pancreatectomized rats. It is believed that the duodenum and jejunum are sites of amylase production even though much of that found in the normal rat's gastrointestinal tract is pancreatic in origin. These surgically treated animals were able to digest starch.