5'-Nucleotidase of rat liver microsomes.

Recent observations from this laboratory have revealed that there is an alteration in the kinetic properties of microsomal glucose 6-phosphatase in the livers of diabetic rats (1, Z), in addition to the’well established increase in total activity (3, 4). Since the kinetic differences between the normal and the diabetic enzyme disappeared upon disruption of the microsomes (Z), it seemed possible that they arose from alterations in the microsomes themselves. In order to obtain more information related to this possibility, an examination of a second microsomal enzyme was undertaken. The phosphatase which hydrolyzes adenosine 5’-phosphate (5, 6) was selected for this purpose. No changes were observed in either the kinetics or activity of thii enzyme in diabetic animals. Pursuant to these studies the specificity and a number of the properties of the enzyme were investigated and are reported herein.