THE RENAL EXCRETION OF INOSITOL BY NORMAL AND DIABETIC RATS 1

Abstract

Depancreatinized and alloxan diabetic rats excrete much more inositol in their urine than do normal rats. Whereas the inositol in the urine of normal rats is little influenced by dietary intake, that of diabetic rats is correlated directly with the amount of inositol ingested. Diabetic rats absorbed inositol faster from the gut than did normal rats. Average inositol level in the blood of diabetic rats after oral inositol was found to be slightly higher than that of normal rats despite an increase in urinary excretion of inositol. An active tubular reabsorption of inositol exists. The reabsorption of inositol is inhibited in diabetic rats, in rats with non-diabetic glycosuria and in phlorizin treated rats. An osmotic diuresis produced by sodium chloride did not result in inosituria comparable to that found in diabetes. It is concluded that the inosituria of diabetes mellitus can be attributed to an increase in the renal clearance of inositol produced by glycosuria.