Analysis of ciliary beat frequency and ovum transport ability in the mouse oviduct

The oviduct is important in reproduction where fertilization occurs, and the fertilized eggs are conveyed to the uterus. Multi-ciliated cells of the oviductal epithelium and muscle contractions are believed to generate this unidirectional flow. Although there are many studies in human oviducts, there are few reports on mouse oviductal ciliary movements where we can dissect underlying genetic programs. To study ciliary movements in the mouse oviduct, we exposed the ovary-side of the oviduct (infundibulum) longitudinally and recorded the ciliary beatings in a hanging drop preparation. We calculated the ciliary beat frequency (CBF) by automated image analysis and found that the average CBF was 10.9 ± 3.3 and 8.5 ± 2.5 Hz (±standard deviation) during the diestrus and estrus stages, respectively. Mapping of the CBF to multiple locations in the epithelium showed that the cilia beat regularly at a local level, but have a range of frequencies within the entire plane. We also observed ova with cumulus cells were transported to the uterus side by the opened oviduct at the diestrus and estrus stages. These results suggest that the ciliated cells of the infundibulum can generate unidirectional flows and are able to deliver ova by their ciliary activities despite their discordance in beating periodicity.