Effect of Long-Term Panthenol Administration on the Pantothenate and Coenzyme A Contents of Rat Tissues. ∗

Summary

Toxicity tests of panthenol show that this biologically active, hydroxy analogue of pantothenic acid has no in vivo antivitamin effect in mammals. In acute toxicity tests, mice tolerated up to 6.25 g per kilo and rabbits up to 3 g per kilo. In chronic feeding tests, 2 mg per day of panthenol had no inhibitory effect upon the growth rate of normal rats on an adequate stock diet and 20 or 500 mg daily produced no histopathological or hematological changes in rats or dogs, respectively. When fed as above at the 2 mg per day level for periods up to 6 months, panthenol did not differ significantly from an equivalent supplement of calcium pantothenate in its effect on rat tissue storage of pantothenate. Total pantothenate in the liver, spleen, kidney and heart, and coenzyme A in the liver were equal or slightly greater in the dosed groups than in the controls. Liver storage in all groups was almost entirely as coenzyme A, and no appreciable amounts of panthenol or free pantothenate accumulated.