Enzyme-activities in serum and plasma of man, dog and rat, and the variation of these enzyme activities during storage of the blood]

The following enzymes were determined in the serum and plasma of man, dog and rat: alanine aminotransferase, asparate aminotransferase, alkaline phosphatase, lactate dehydrogenase and alpha-hydroxybutyrate dehydrogenase. The enzyme assays were performed on an Eppendorf-Enzymautomat 5010 using optimised conditions at 25 degrees C. The enzyme-activities changed by variable amounts during standing of the blood. This concerned mainly lactate dehydrogenase, alpha-hydroxybutyrate dehydrogenase and aspartate aminotransferase in the serum of the rat. In human serum and in dog serum, and in the plasma of man, dog and rat this effect was only less pronounced.