Is follicle atresia regulated by Activin, Inhibin, and estradiol pathway?

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K06241
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 44040:Morphology and anatomical structure-related
• Research Institution: Hokkaido University
• Principal Investigator: OGIWARA Katsueki 北海道大学, 理学研究院, 准教授 (00422006)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: 濾胞選択 / 濾胞閉鎖 / アクチビン / インヒビン / エストロゲン / エストロゲン受容体

Outline of Final Research Achievements

The objective of the present study is to investigate the details of the inhibitory mechanism of follicle atresia by the hormone reagent, which is suggested to exert an inhibitory effect on the follicle atresia during folliculogenesis. Our previous study has suggested that activin, inhibin and estradiol (E2) were involved in the atresia. In this study, we examined in more detail how the factors are associated with the atresia. An anti-inhibin antibody contained in the hormone reagent inhibits the activity of inhibin A. In this case, activin A exerts its activity through the receptor, resulting in the accumulation of E2 in the follicles and the upregulation of the estrogen receptor a (ERa) expression in the granulosa cells of the follicles. We found that the accumulation and the upregulation probably played important roles in the inhibition of the atresia. This is the most significant founding in this study.

Free Research Field

生殖生物学

Academic Significance and Societal Importance of the Research Achievements

濾胞内顆粒膜細胞においてエストロゲン受容体が発現している濾胞が濾胞閉鎖を免れる可能性が高いことを発見したことが本研究の最も重要な成果である。一回の排卵で1個の卵を排卵する種（ウシやヒツジなど）において濾胞閉鎖機構のモデルが提唱されているが、これらの種とは異なる機構で濾胞閉鎖が調節されている可能性があることを見出した点は学術的にとても意義のある成果であると考える。