Morphology of the rat uterus after long-term treatment with progesterone antagonists

Rumpel E, E. Rumpe, E Rumpel, Michna H, H. Michna, Kühnel W, W Kühne, W Kühnel
Annals of anatomy = Anatomischer Anzeiger : official organ of the Anatomische Gesellschaft · 1993 · vol. 175(2) , pp. 141–149 · doi:10.1016/s0940-9602(11)80170-6 · PMID:8489034 · W2059015734
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This paper investigates the morphological changes in the rat uterus following prolonged administration of progesterone antagonists.

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Abstract

The effects of long-term treatment with the progesterone antagonists ZK 98.299 and ZK 112.993 on the uterus of intact mature rats were investigated with light and electron microscopy. After 3-4 weeks treatment with both progesterone antagonists, the uterine luminal epithelium showed ongoing mitotic activity, increased apoptosis and invasion by granulocytes. Many uteri showed metaplastic areas with stratified squamous epithelium. Basically, the same changes occurred, but to a lesser extent, in the glandular epithelium. At the ultrastructural level, the epithelial cells displayed the morphological features of a certain degree of differentiation. The dissociation of collagen fibres, infiltration by granulocytes and dilatation of small vessels were observed in the subepithelial connective tissue. The myometrium increased in thickness and electron microscopic examination revealed hypertrophic myocytes with a well developed granular endoplasmic reticulum. Most of the morphological reactions may be regarded as due to the direct inhibitory action of progesterone antagonists at the level of the different uterine tissues and the resulting unopposed action of estrogen. The metaplastic changes and the suppression of the anti-proliferative action of progesterone on uterine epithelial cells should be taken into account when treating women in their reproductive years with these drugs for long periods of time, as may be necessary for the endocrine treatment of mammary cancer and endometriosis.

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MeSH descriptors

Endometrium Gonanes Mifepristone Progesterone Uterus Animals Cytoplasmic Granules Cytoplasmic Granules Cytoplasmic Granules Endometrium Endometrium Endometrium Epithelial Cells Epithelium Epithelium Epithelium Female Gonanes Microscopy, Electron Mifepristone

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References (47)

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SciLite annotations

organisms 2
zitter rats rattus sp.
chemicals 6
progesterone progesterone progesterone progesterone estrogen progesterone

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