Changes in vascular permeability and deciduoma formation during the peri-implantation period of the rat in response to exogenous gonadotropins

Abstract

Background Permeability of thin‐walled vessels of the endometrium could be a prerequisite for deciduoma formation. Exogenous gonadotropins alter endometrial morphology and inhibit vascular permeability on the day of implantation. The aim of this study was to investigate the effect of exogenous gonadotropins on vascular permeability in the peri‐implantation period and relate this to deciduoma formation. Methods Female rats were hyperstimulated with follicle‐stimulating hormone and human chorionic gonadotropin prior to mating. Control animals were not injected. Endometrial tissue was collected at 4.5, 5.5, and 6.5 days after mating. Tissue was processed for electron microscopy. Results The presence of thin‐walled fenestrated vessels and decidualised stromal cells were found in all control groups. With the exception of one fenestration, which occurred in a vessel from one hyperstimulated animal on 5.5 days of pregnancy, no fenestrations were found in the vessels of hyperstimulated animals. Decidualisation of stromal cells did not occur in these animals. Conclusion Hyperstimulation with exogenous gonadotropins inhibits vascular permeability and subsequent decidualisation. Implantation thus fails to occur. Anat. Rec. 247:20–24 © Wiley‐Liss, Inc.

The effect of hyperstimulation on transforming growth factor β1 and β2 in the rat uterus: possible consequences for embryo implantation

“…However, other characteristics important for implantation, such as the decidual reaction, oedema and obliteration of the lumen, as well as close contact of the opposite sides of the luminal epithelium were not observed in these animals. The above mentioned findings support the work by Kramer (1997), who showed that absence of decidualization in the rats that underwent ovarian hyperstimulation is due to a decrease in vascular permeability, which is an indispensable condition for deciduomata formation.…”

“…high levels of oestrogen, have harmful effects on the endometrial morphology such as increased stromal vascularity and luminal dilatation (Spaziani, 1963), a decrease in the vascular permeability of the endometrium (Kramer, 1997) and an absence of decidualization of the subepithelial stromal cells (Stein and Kramer, 1989). Although detailed observations of stromal vascularity and vascular permeability were not included in the present study, similarities are present between results found in the current study and the findings of Kramer (1997). Firstly, the presence of the pontamine blue reaction in 4.5 (only one control animal), 5.5 and 6.5 days control animals demonstrated an increase in the permeability of uterine vessels, which is according to Psychoyos (1973) an indispensable condition for deciduoma formation.…”

“…Administration of exogenous hormones is found to increase the amount of circulating oestradiol prior to implantation (Kramer, 1990), affect the progesterone: oestradiol ratio (Kramer et al, 1993, Kramer andde Wet, 1994), decrease the vascular permeability of the endometrium (Kramer, 1997), prevent decidualization of the subepithelial stromal cells (Stein and Kramer, 1989) and reduce carbohydrates in the glycocalyx of the endometrium (Kramer and de Wet, 1994;Peverini and Kramer, 1995).…”

Leptin induces vascular permeability and synergistically stimulates angiogenesis with FGF-2 and VEGF

“…In contrast to leptin, CRH reduces vascular permeability (22)(23)(24). In addition, gonadotropin, another endocrine hormone, also reduces vascular permeability (25). Thus, it is possible that vascular permeability in an organ represents the balanced status controlled by both vascular permeability enhancing and inhibitory factors.…”

Spectrotemporal changes in electrical activity of myometrium due to recombinant follicle-stimulating hormone preparations follitropin alfa and beta

“…So the decrease in stromal decidualization is a negative factor for fertility (30), and FSH could inhibit the proliferation of endometrium (31) via its receptors found in stromal cells (32). Therefore, recombinant human FSH administration may disturb the synchronization between embryo and endometrium, resulting in implantation failure (19,30,33). No significant decidualization was detected in individual animals, which may lead to speculation (see Table 3).…”