Localization of lectin binding sites on the rat intestinal microvillous membrane

The distribution of peroxidase labeled Asparagus Pea Lectin and Soybean Agglutinin on the rat intestinal microvillous membrane was studied. Controls were carried out to determine the reaction specifity . Some analogy was established between the distribution of the binding sites of both lectins. The reaction product was deposited mainly on the microvillous membrane of the crypt cells and the cells from the lower part of the intestinal villi, and to a lesser extent on the upper part of the latter. Electron dense material was seen on the upper part and chiefly on the tip of the microvilli. From the results of this study and on the basis of data from our previous studies it was proposed, that changes in the carbohydrate content of the microvillous membrane appear during the differentiation and maturation of the intestinal cells.