Studying the Dynamic Process of Rat Ovary Through Histological Sections and Cell Culture

Abstract

Background: Primordial follicles, which are the structural units of the ovary and represent the ovarian reserve, continue their development by entering into paracrine, endocrine, and cell-cell interactions with the structures and cells in the niche. Objectives: To examine the development of cells and structures in the ovary in cell culture medium and histological sections and observe the effects of the niche they formed on folliculogenesis. Methods: Three 3-week-old as the first group for cell culture, and three 8- to 10-week-old (early reproductive period) and three 12- to 14-month-old (late reproductive period) Wistar albino rats as the second and third groups for histologic sections were included in our study. To prepare histological sections, ovarian tissues of rats in the early and late breeding periods were excised and passed through routine histological tissue process steps. Additionally, ovarian surface epithelium proliferating together with ovarian stromal cells in explant cell culture was isolated and multiplied. Results: Ovarian surface epithelium and stromal cells were observed to proliferate in cell culture. Primordial follicle-like structures were observed between the surface epithelial cells. Histological examination revealed periovary adipose tissue around the ovary, separated from the surface epithelium by a thin fibrous sheath. It was observed that primordial follicles were located in the tunica albuginea layer. The fibroblast-like mesenchyme in the tunica albuginea of the corpus luteum formed after ovulation thickens this layer by the proliferation of cells and creates a suitable environment for developing primordial follicles. Also, the tubules of the rete ovarii, which emerge during the formation of the genitourinary system in the embryological period, continue to exist in the ovaries and mesovarium in rats in the early and late reproductive period. Conclusion: The presence of tubules of the rete ovarii in the ovary and mesovarium during the reproductive period may indicate that these structures are also important in folliculogenesis. Copyright © 2025 The Author(s)