Na/K-ATPase Activity and Ketone Body Metabolism in Long-term Diabetic Rats

Abstract

The long-term (34 weeks) effect of streptozotocin induced diabetes was assessed in Wistar rats.Na + /K + -ATPase activity was measured by ouabain inhibitable 86 Rb + -uptake into erythrocytes. No difference in the rate of Rb + -uptake, the K m for Rb + or the K i for ouabain was detected between normal and diabetic rats. Thus, the change in Na + /K + -ATPase activity repeatedly described in short-term studies may not translate into a long term physiologically relevant change in ion flux through the sodium pump.Rats excrete ketone bodies mainly as β-hydroxybutyrate. This compound does not show up with nitroprusside sodium based test sticks, it can however be detected by coupled spectrophotometric assay with hydroxybutyrate dehydrogenase.Almost half of the diabetic animals reverted to a non-diabetic state during the experiment, followed by at least partial reversal of secondary diabetic damage.