Ulex europeus agglutinin I binding pattern during chemical carcinogenesis in the rat gastrointestinal tract



Background. Fluorescein isothiocyanate–Ulex europeus agglutinin I stain (UEA1) was postulated as a prominent histochemical marker for premalignant mucosa in dimethylhydrazine (DMH)–treated animals. UEA1 (evaluated by two scanning methods) and high iron diamine Alcian blue (HIDAB) stain were used in attempt to detect premalignant colonic mucosa in this animal model. The authors also examined the influence of the duodenal medium on colonic segments transposed to the upper gastrointestinal tract.

Methods. Rats were placed into three groups: those with interposed intestine, those receiving the sham operation, and controls. Half of the animals received DMH, and surviving rats were killed at 2, 4, and 8 months.

Results. The authors found no differences in tumor development in the transposed and nontransposed colons of animals treated with DMH. Several transposed segments of animals without carcinogen induction showed dysplastic areas. These findings suggest a trophic role of certain duodenal factors in the epithelial kinetics of the transposed colons. The authors did not find HIDAB stain useful in the identification of premalignant colonic mucosa. The quantitative evaluation method of UEA1 binding was more reliable. Fifteen percent of all the colon specimens of animals without chemical induction were stained with UEA1 with this form of evaluation. Positive staining of the interposed colon samples was the most important factor for these findings.

Conclusions. In this animal model, UEA1 staining is a potentially useful marker of premalignant mucosa, particularly when the nontransposed distal colon of animals treated with DMH is considered.