Mucosal Adsorption and Absorption of Vitamin B 12 in the Intestine of the Rat

Abstract

Summary

Using the rat intestinal loop technic, it was demonstrated that a large part of a physiological dose of Co⁶⁰-B₁₂ was adsorbed to the mucosal surface in the presence of rat intrinsic factor (IF) at a faster rate than it was without IF, and ethylenediamine-tetraacetate markedly inhibited this in vivo adsorption. The early mucosal adherence of Co⁶⁰-B₁₂ did not represent transmucosal absorption, and transserosal absorption was further delayed. It was concluded that there are at least 2 kinds of surface adsorption; one represents a phase of physiological absorption involving IF, and the other, a nonabsorptive process.