Distribution of Serum Amylase in Man and Animals

Abstract

Many enzymes formerly viewed as single entities are now considered to be composed of a number of molecular forms termed isoenzymes.¹ Although each of these isoenzymes acts on the same substrate and produces the same end product, they show certain physicochemical differences. Evidence has recently been advanced indicating that this concept of enzyme multiplicity may be extended to serum amylase.² Such observations may have clinical significance, since serum total amylase as conventionally determined is relatively nonspecific. Serum amylase activity may be altered in such varied disorders as pancreatitis, perforated peptic ulcer, liver and biliary disturbances, peritonitis, intestinal obstruction, and ruptured ectopic pregancy.³ The level of amylase activity in the serum may also be increased by administration of opiates and analgesic drugs.⁴ If it should prove possible, therefore, to delineate distinctive isoenzymes of amylase and to determine their specific tissue sources, the usefulness of serum amylase in