Interaction between Spermatozoa and the Different Epithelia along the Female Reproductive Tract of Mustelus schmitti

Abstract

The presence of sperm was observed in different organs of the reproductive tract of M. schmitti. These were the club, baffle and terminal zone of the oviducal gland, posterior portion of the uterus and in the cervix. This fact allowed for consideration not only its storage but its interaction with the female reproductive tract epithelia as well. SEM (microscopic observation studies) detected loose and sole spermatozoa in the club and baffle zones in a pregnant female. On the other hand, histochemical techniques showed sperm storage tubules of the terminal zone, which contain bundles of sperm, do not stain AB (alcian blue) or PAS (periodic acid schiff). Disintegration of some of the male gametes was observed in the posterior part of the uterus with TEM (transmission electron microscopy) studies which would indicate a first uterine sperm selection. The uterine epithelial cells involved in this process showed an important level of secretion vacuoles suggesting an interaction with sperm cells. Sperm in the cervix was found without the matrix that constitutes the spermatozeugmata formed in the male tract. Some heads of the sperm were uncurled while they were interacting with the cervical cells. Key