Cyclic changes in the ampulla of the rat oviduct

Abstract

The mammalian oviduct especially the ampulla part plays an essential role in female reproduction as fertilization, oocyte maturation and early embryonic development. The present study was focused on the microscopic changes of the rat ampulla epithelium during the oestrous cycle and correlates the findings with their possible functions. Twenty five rats of regular 5 day oestrous cycles were used in our study. They were divided into 5 groups; five rats in each phase of estrous cycle (early proestrus, late proestrus, estrus, metestrus and diestrus). They were sacrificed and the ampullae were excised, fixed and processed to be examined by light and electron microscopy. Marked changes in both relative number and the structure of ciliated and secretory cells throughout the estrous cycle were seen. Ciliated cells were increased in the relative number at the early proestrus till became the predominant cell type at the late proestrus then decreased at the estrus phase accompanied by deciliation. The secretory cells increased in the relative number and prevailed at the metestrus with increasing in the secretory activity. They became rare at the diestrus, a day on which the first sign of neociliogenesis was recorded. Intra epithelial glands were firstly appeared at the estrus phase which increased in number and size at the metestrus. The secretory material is showed PAS positive reaction in the estrus and the metestrus.

Follistatin-like-1, a diffusible mesenchymal factor determines the fate of epithelium

“…Both secretory and ciliated cells coexist in the epithelium of the cranial oviductal region, whereas the majority are secretory cells in the caudal oviductal region. The present study dose not support an earlier idea that cilial and secretory epithelial cells are transitory throughout the estrous cycle (39)(40)(41). To explain lineage determination and the cellular distribution pattern, there must be at least two signals released from the neonatal mesenchyme.…”

Expression of Leptin and Adiponectin in the Rat Oviduct

“…Staining intensity in the ampulla increased from proestrous to estrous, suggesting that ovarian steroids regulate leptin and adiponectin expression. These results are consistent with the rapid cyclic changes easily recognized in the gross morphology of the rat oviduct and that are most evident in the ampulla (Shirley and Reeder 1996). In this region, ciliated epithelial cells prevail before ovulation, whereas secretory cells are more numerous at the postovulatory stages.…”

Alterations in Cell Proliferation and Morphology of Ampullar Epithelium of the Mouse Oviduct during the Estrous Cycle.

“…Non-ciliated secretory cells were predominant among ampullar epithelial cells in estrus after ovulation, and the percentage became highest in metestrus, rapidly decreasing in diestrus. The changes in constitution of ampullar epithelium observed in this study were similar to those reported in rats [6,19]. In hamsters [5], such secretory cells are predominant on the day of ovulation.…”