Hydrolysis and Absorption of Pantothenate and Its Coenzymes in the Rat Small Intestine

Abstract

The transport of pantothenate by the rat small intestine occurs by simple diffusion. There was no significant difference in the rate of in the upper, middle or lower sections of the intestine. Coenzyme A was hydrolyzed to pantetheine and pantothenate in the intestinal lumen via the following series of reactions: coenzyme A → phosphopantetheine → pantetheine → pantothenate. Intestinal tissue, which contains high levels of pantetheinase, quickly degrades pantetheine to pantothenate, which is then transported to the blood and thence to other tissues. Tissue distribution patterns of ¹⁴C 5 hours after intraluminal administration of ¹⁴C-labeled coenzyme A or [¹⁴C]pantothenate were similar; approximately 40% of the ¹⁴C was present in muscle and 10% in liver.