Anatomy and histology of the foramen of ovarian bursa opening to the peritoneal cavity and its changes in autoimmune disease‐prone mice

Abstract

The ovaries originate from the gonadal primordium, located in the lumbar region on the medial surface of mammalian mesonephros (König et al., 2009). Moreover, the oviducts and uterus develop from the müllerian ducts (Yamamoto et al., 2018) and play crucial roles in female reproduction. The ovaries and oviducts are suspended within the mesovarium and mesosalpinx, respectively.

Ovulation Enhances Intraperitoneal and Ovarian Seedings of High-Grade Serous Carcinoma Cells Originating from the Fallopian Tube: Confirmation in a Bursa-Free Mouse Xenograft Model

“…It helps to confine the ovulated oocytes and facilitate the catch-up by the oviduct infundibulum. Although the small opening (of approximately 0.04 to 0.12 cm 2 [ 15 ]) of the foramen of the ovarian bursa located at the proximal mesosalpinx allows limited drainage, the majority of ovulatory FF and oviduct fluid flowing into the uterine cavity instead of the peritoneal cavity after ovulation [ 15 , 18 ]. It is thus assumed that the bursa structure, on one hand, interferes with the release of FF-carcinogens into the peritoneum and, on the other hand, with the seeding of exfoliated cancer cells into the ovary.…”

“…Before experimental proof is feasible, an anatomic barrier in the murine reproductive system must be overcome. In rodents, a bursa structure envelops the ovaries and distal oviduct [ 15 ] and interferes with the direct communication of FF with the peritoneal cavity after ovulation [ 16 ]. The presence of ovarian bursa in mouse not only prevents the direct release of ovulatory FF into the peritoneum but may also hinder the seeding of exfoliated STIC cells into the ovary.…”

Multiple cell types in the oviduct express the prolactin receptor

“…Both SF3 and LF PRLR localize to cilia and one can see STAT5 tyrosine phosphorylation within cilia, thereby suggesting that the PRL to which these receptors are responding is within the oviduct. Experimentally, this would have come from the peritoneal fluid through the bursal foramen 41 . Physiologically, the PRL could also be delivered via this route, could be a transudate from plasma, or could come from follicular fluid or cells of the ovulated mass 42,43 .…”

“…Experimentally, this would have come from the peritoneal fluid through the bursal foramen. 41 Physiologically, the PRL could also be delivered via this route, could be a transudate from plasma, or could come from follicular fluid or cells of the ovulated mass. 42,43 No production of PRL by oviduct cells was detected by either single cell RNAseq or RT-qPCR of the individual segments (negative data not presented) and so the PRLRs are not responding to autocrine/paracrine PRL.…”