Dose Dependent Effects of D-Sorbitol on Intestinal Absorption of Vit. B 12 . ∗

Abstract

Summary

The effect of D-sorbitol on intestinal absorption of Co⁶⁰B₁₂ was studied in rats. The data demonstrated that sorbitol, when given by mouth in large quantities together with supraphysiological doses of B₁₂, enhanced absorption of B₁₂ in intact animals. However, absorption of small, physiological doses of B₁₂ was reduced by the same dose of sorbitol. The dependence of the sorbitol effect on the B₁₂ dose may be explained on the basis of the 2 different mechanisms for B₁₂ absorption. No intrinsic factor activity was demonstrated in sorbitol as studied with isolated intestinal loops. When the cecum was excluded from the absorptive route by ileostomy, the conditions that increased absorption in intact animals resulted in reduction of absorption. Possible involvement of the cecum and the altered physiological state of the intestinal contents in enhancement of B₁₂ absorption by sorbitol have been discussed.