Mechanism for acute reduction of 1,5-anhydroglucitol in rats treated with diabetogenic agents.

The mechanism for acute reduction of plasma 1,5-anhydroglucitol (AG) in experimental diabetic rats was studied. Acute AG decrease was induced not only by diabetogenic agents, such as streptozotocin (STZ) and alloxan, but also by phloridzin, which caused glucosuria but not hyperglycemia. A similar reduction also occurred in hyperglycemia induced by glucose injection. The AG reduction induced by STZ was completely abolished by bilateral nephrectomy or by euglycemia with insulin treatment. The decrease of plasma AG was well correlated with the degree of urinary excretion of AG, which in turn reflected the degree of urinary glucose excretion, irrespective of the kind of agent causing the glucosuria. Under conditions of continuous glucose infusion, AG concentration decreased not only in plasma but also in various tissues and organs. The amount of AG lost was estimated to be almost equal to that excreted into urine during the period of infusion. These observations suggest that the degree of reduction of plasma AG depends simply on the urinary excretion of glucose, and it was assumed that the urinary excretion of 0.5 mg AG corresponds to the urinary excretion of 100 mg glucose during a short period after the onset of glucosuria.