American Journal of Clinical Nutrition, Vol 20, 960-967, Copyright © 1967 by The American Society for Clinical Nutrition, Inc.

Urinary Excretion of Pantothenic Acid by Diabetic Patients and by Alloxan-Diabetic Rats

¹ Nutrition Fellow, Department of Internal Medicine, University of Iowa, Iowa City, Iowa
² Professor, Department of Internal Medicine, University of Iowa
³ Professor and Head, Radiation Research Laboratory, University of Iowa
⁴ Graduate student, Radiation Research Laboratory, University of Iowa
⁵ Professor and Head, Internal Medicine, University of Iowa
⁶ Research Professor, Department of Internal Medicine, University of Iowa

Studies in Patients

Pantothenic acid (PaA) metabolism was studied in 11 patients with diabetes melitus with the following results:

1) Even when diabetic control was maintained, the rate of urinary excretion of PaA was abnormally high.

2) When diabetic ketosis was induced in three patients by insulin withdrawal, the excretion rate of PaA increased greatly.

3) This increased rate of PaA excretion in diabetic ketosis could not be accounted for solely on the basis of polyuria; hence a metabolic mechanism is suspected.

4) There was no significant decrease in blood concentrations of PaA in diabetic patients.

Studies in Animals

1) Both diuretic (Diuril)-treated and diabetic (alloxan) animals excreted abnormally large amounts of radioactivity derived from ¹⁴C PaA. This loss could be ascribed to diuresis alone and may have accounted for the low plasma levels of ¹⁴C PaA observed 24 hr after administration.

2) By contrast, microbiologic assays disclosed a greater rate of PaA excretion by diabetic animals than could be accounted for on the basis of diuresis alone. We suspect that another expelling mechanism operated in diabetic conditions. Microbiologic assay for PaA in blood from these animals gave normal values. The differences between metabolism of injected PaA and PaA from normal sources are discussed.

3) Both microbiological and radioactive assays gave high values for PaA in the liver and kidneys of the diabetic rats. Concentrations of PaA in other organs are reported.