title: The effect of concanavalin A and wheat germ agglutinin on the ultrastructure and permeability of rat intestine. A possible model for an intestinal allergic reaction.
abstract: Sprague-Dawley rats were exposed to lectins, either concanavalin A (Con A) or wheat germ agglutinin (WGA). The lectins were instilled into a ligated segment of the distal small intestine together with permeability markers, fluoresceinated dextran (MW 3,000) or a mixture of differently sized polyethylene glycols (MW 400, 600 and 1,000). WGA-treated rats showed a decreased permeability to small molecules (MW less than 600) of polyethylene glycol but an increase for a larger dextran molecule (MW 3,000). These effects as well as the morphological findings might mimic the situation in patients with food allergy or celiac disease. Con A-treated rats had decreased intestinal permeability to the larger dextran molecules (MW 3,000), whereas the passage of small molecules was unaffected and the ultrastructural effects were minute. The Con A-induced changes could result from a mucotractive effect, associated with a low-grade gut allergy. These observations suggest that lectins can affect both the ultrastructure and the permeability of the intestine, in a way assumed to mimic allergic reactions to food constituents.
mesh_terms: D000818:Animals; D003208:Concanavalin A / Q000276:immunology*; D003911:Dextrans / Q000652:urine; D005260:Female; D005470:Fluorometry; D007421:Intestine, Small / Q000648:ultrastructure*; D037102:Lectins / Q000276:immunology*; D008970:Molecular Weight; D010539:Permeability; D037121:Plant Lectins; D011092:Polyethylene Glycols; D051381:Rats; D011919:Rats, Inbred Strains; D014908:Triticum
chemical_list: D003911:Dextrans; D037102:Lectins; D037121:Plant Lectins; D003208:Concanavalin A; D011092:Polyethylene Glycols