Anatomy and histology of the foramen of ovarian bursa opening to the peritoneal cavity and its changes in autoimmune disease‐prone mice. Issue 1 (1st September 2020)

• Record Type: Journal Article
• Authors: Hosotani, Marina; Ichii, Osamu; Nakamura, Teppei; Namba, Takashi; Islam, Md. Rashedul; Elewa, Yaser Hosny Ali; Watanabe, Takafumi; Ueda, Hiromi; Kon, Yasuhiro
• Is Part Of: Journal of anatomy. Volume 238:Issue 1(2021)
• Page Start: 73
• Page End: 85
• Publication Date: 2020-09-01
• Subjects: 3D morphometry -- mesosalpinx -- ovarian bursa -- oviduct -- reproduction; Anatomy -- Periodicals; 571.3
• DOI: 10.1111/joa.13299
• Languages: English
• ISSNs: 0021-8782

Abstract

Abstract: The ovarian bursa is a small peritoneal cavity enclosed by the mesovarium and mesosalpinx, which surrounds the ovaries and oviductal infundibulum in mammals. The ovarian bursa is considered as the structure facilitating the transport of ovulated oocytes into the oviduct. Our previous study revealed reduced oocyte pick‐up function in the oviduct of lupus‐prone MRL/MpJ‐Fas lpr / lpr mouse, suggesting the possibility of an escape of ovulated oocytes into the peritoneal cavity, despite the presence of an almost complete ovarian bursa in the mouse. In this study, we revealed anatomical and histological characteristics of the ovarian bursa in C57BL/6 N, MRL/MpJ, and MRL/MpJ‐Fas lpr / lpr mice. All strains had the foramen of ovarian bursa (FOB), with a size of approximately 0.04 to 0.12 cm 2, surrounded by the ligament of ovarian bursa (LOB), which is part of the mesosalpinx. The LOB was partially lined with the cuboidal mesothelial cells and consisted of a thick smooth muscle layer in all strains. In 6‐month‐old MRL/MpJ‐Fas lpr / lpr mice, in which the systemic autoimmune abnormality deteriorated and oocyte pick‐up function was impaired, the size of the FOB tended to be larger than that of other strains. Additionally, in MRL/MpJ‐Fas lpr / lpr mice at 6 months of age, there was infiltration by numerous immune cells in the mesosalpinx suspending the isthmus; however, the LOB prevented severe inflammation and showed deposition of collagen fibers. These results not only indicate that the FOB is a common structure within mice, but also imply the physiological function of the LOB and its role in maintaining the microenvironment around the ovary, as well as regulating healthy reproduction. Abstract : The mesosalpinx connecting oviduct and the cranial part of uterus has the silt‐like opening of the ovarian bursa to the peritoneal cavity, which is called the foramen of ovarian bursa. The ligament of ovarian bursa, which is the part of the mesosalpinx connecting the oviduct and uterus, surrounds the foramen of ovarian bursa and consists of the smooth muscle layer. Autoimmune disease‐prone mice show morphological alternations in the ligament of ovarian bursa.