Ultrastructural demonstration of cilia and ciliary rootlets in mammalian uterine tube epithelium in different functional states.
Tissue from the infundibulum region of the uterine tube (oviduct) of guinea pigs, cattle, sheep, and swine was examined by electron microscopy. In all specimens, cilia and ciliary rootlets were present in variable numbers in the ciliated cells during both the follicular and the luteal phases of the estrous cycle. True degeneration of cilia was not evident during luteal phase or pregnancy. The ciliary rootlets in ruminant and nonruminant species had structural similarities to those described in people and rhesus monkeys. These organelles measured approximately 1 mum long in most species studied, but in the cow, the rootlets, extending downward into the cytoplasm from the proximal end of the basal body, reached a length of 2 mum. The rootlets had a cross-striation of thick and thin bands, the period measuring 40 to 60 nm. Mitochondria were closely associated with the rootlets. The rootlets usually formed a small angle to the axis of the cilium. These organelles probably function as anchoring or stabilizing structures for the motile cilia. Results indicated that the rootlets are more widely distributed in mammalian uterine tube cilia than previously postulated. Polyribosomes, microfilaments, microtubules, and electron-opaque fibrous granules were frequently seen in the cytoplasm of the ciliated cells. The presence of fibrous granules in close association with the basal bodies indicate that these granules have a role in the development of cilia and rootlets. Cilia and precursor fibrous granules were also seen in porcine fetal uterine tube epithelial cells.
D000818:Animals; D002417:Cattle / Q000502:physiology; D002923:Cilia / Q000648:ultrastructure; D003594:Cytoplasmic Granules / Q000648:ultrastructure; D004847:Epithelial Cells; D004848:Epithelium / Q000648:ultrastructure; D004971:Estrus; D005187:Fallopian Tubes / Q000502:physiology / Q000648:ultrastructure*; D005260:Female; D006168:Guinea Pigs / Q000502:physiology; D011247:Pregnancy; D012756:Sheep / Q000502:physiology; D013552:Swine / Q000502:physiology