The zoapatle. VIII. Ultrastructural changes in endometrium of rats

Intrauterine administration of Zoapatle aqueous crude extract (ZACE) prepared from Montanoa tomentosa s.s.p. tomentosa, on day 4 of pregnancy, did not alter the normal uterine morphological changes by days 5 and 8 of pregnancy in the rat. On the other hand, ZACE made from Montanoa frutescens caused profound alterations on the uterine structures, such as: focal loss of epithelial lining, thickened blood vessels and alterations in stroma cells in rat endometrium. Morphological alterations correlate well with the antiimplantation effect associated with the intrauterine administration of these plant extracts. Scanning electron micrographs of leaves from Montanoa tomentosa and Montanoa frutescens revealed striking differences in glandular secretion and trichomes.