Lectin binding patterns of uterine glands in mares with chronic endometrial degeneration

Objective-To evaluate changes of glycoconjugate in uterine glands of endome trial tissues obtained from mares. Animals-50 adult mares. Procedure-Uterine biopsy samples were collected during the breeding season and analyzed histologically for signs of chronic endometrial degeneration. Stage of the estrous cycle was established, using clinical examination and determination of hormonal status. Uterine tissue samples were analyzed, usi ng lectin histochemical and immunohistochemical techniques (estrogen and pr ogesterone receptors). Connective tissues were stained to determine alterat ions of ground substance in periglandular fibrosis. Results-Of 50 mares, 30 (60%) were classified as normal or having modest al terations, and 20 (40%) were classified as having moderate or severe endome trial degeneration. In normal equine endometrium, several lectins (Helix po matia agglutinin, Lotus tetragonolobus agglutinin, Ricinus communis I agglu tinin, Ulex europaeus agglutinin, and wheat germ agglutinin) bound to glyco conjugates of the luminal epithelium and openings of uterine glands. Lectin binding patterns of cystic dilated glands or fibrotic glands in endometria l samples were remarkably strong, whereas normal surrounding cells remained unstained. Lotus tetragonolobus lectin was not suitable for detecting endo metrial alterations. Connective tissues stained with Alcian blue and result s of Hale colloidal-iron binding revealed acidic ground substance in perigl andular fibrosis. Estrogen and progesterone receptors were evenly distribut ed in healthy and affected endometrial samples. Conclusions and Clinical Relevance-Glyco-conjugate patterns of uterine glan ds were altered in mares with chronic endometrial degeneration. Therefore, uterine secretions are likely to be altered. These changes are not induced by changes in content of estrogen and progesterone receptors in endometrial tissues.