Fine structural changes of the porcine uterine tube epithelium during early and late pregnancy
Nayak, R.K.; Albert, E.N.; Kassira, W.N.
American Journal of Veterinary Research 37(12): 1421-1433
1976
ISSN/ISBN: 0002-9645 PMID: 999069 Document Number: 98348
The oviducts of 16 gilts were removed and examined at gestational ages of 31, 36 or 101-112 days. With light microscopy, the epithelium at all stages appeared similar to that of the luteal phase of the ovulation cycle, when the corpora lutea were fully grown, but ultrastructural changes were apparent. The cytoplasm of the stromal cells contained a prominent nucleus, and rough endoplasmic reticulum of tubular form. Active cilia were present throughout pregnancy and numerous polyribosomes, mitochondria and microtubules were seen in the cytoplasm of the ciliated cells. Fibrogranular aggregates, thought to be involved in the formation of cilia, were associated closely with basal bodies. The time of appearance of these granules could be correlated with increasing endogenous levels of plasma oestrogen. None of the changes in secretory cells, characteristic of the oestrous cycle, were seen in early or late pregnancy.