ENDOMETRIUM: FROM NUCLEAR RECEPTORS TO TEST MODELS OF NEW DRUGS
Introduction. Endocrine factors are considered to be important in the etiology of spontaneous abortion.
Aim of the study. Histological and immunohistochemical characterization of the expression of estrogen and progesterone receptors in
the gravid endometrium during the first trimester of non-developing pregnancy under the treatment by progesterone analogues.Comparative
experimental evaluation of gestagenic activity of micronized progesterone and didrogesterone on the animal model.
Results. The study has revealed a decrease of the expression of progesterone receptors in the decidual tissue and an increase of the
expression of estrogen receptors in the glands and decidual tissue. The receptor imbalance in case of polytherapy by analogues of progesterone
has been found to be more prominent than that in case of monotherapy. Using an experimental animal model, it was revealed that both
dydrogesterone and micronized progesterone can cause the secretory transformation of the endometrium, but dydrogesterone was found to be
more efficient than micronized progesterone.
Conclusion. Comparative experimental evaluation of gestagenic activity of micronized progesterone and didrogesterone has revealed the
ability of both preparations to cause the secretory transformation of the endomentrium, however, pharmacological efficiency of didrogesterone
was higher. Hormonal treatment of spontaneous abortion by progesterone analogues often does not have expected result that can be explained
by excessive hormonal load leading to the endometrial receptor imbalance and inadequate tissue reaction to the hormonal therapy.
Keywords:
non-developing pregnancy, estrogen and progesterone receptors, micronized progesterone, dydrogesterone, animal model, secretory transformation of the endometrium