title: [Endometrial cups in horses].
abstract: Endometrial cups in horses are outgrowths appearing in the uterine wall of the pregnant horn between approximately 38 days and 150 of gestation. The cups are structures which vary in shape from oval to irregular and have distinct raised edges, showing an ulcer-like form. The maximum measurements are approximately 5 X 2.5 X 2.5 cm. Microscopic examination shows that they consist of large epithelioid decidual-like cells having large nucleoli. Pregnant Mare Endometrium Gonadotrophin (PMEG) is produced in the endometrial cups. PMEG may be regarded as a precursor of Pregnant Mare Serum Gonadotrophin (PMSG), which can be detected in the blood of mares. The exact function of PMSG is still obscure; some possible functions are suggested in the present paper. After approximately 70 days of gestation, regression starts. The regression of the cups is an immunological process in which the cellular branch of the immunological system plays an important role. Humoral immunity plays a more protective role in the process of regression, probably as a result of the production of 'blocking' antibodies.
mesh_terms: D000818:Animals; D000954:Antigens, Surface / Q000276:immunology; D004717:Endometrium / Q000033:anatomy & histology* / Q000276:immunology / Q000502:physiology; D005260:Female; D006064:Gonadotropins, Equine / Q000096:biosynthesis* / Q000502:physiology; D006736:Horses / Q000033:anatomy & histology* / Q000276:immunology / Q000378:metabolism; D008214:Lymphocytes / Q000276:immunology; D011247:Pregnancy; D011270:Pregnancy, Animal / Q000502:physiology*
chemical_list: D000954:Antigens, Surface; D006064:Gonadotropins, Equine
vernacular_title: De endometriumcups bij het paard.