Immunolocalization And Distribution Pattern of Estrogen (ERα and ERβ) and Progesterone (PR) Receptors along the Excurrent Duct of Male Greater Cane Rat (Thryonomys swinderianus)

The excurrent duct, which plays vital roles in the reproductive biology of all male mammals, shows some structural variations among different species. Some hormones such as testosterone, estrogen and progesterone, through their different receptors, have been known to be involved in the normal functioning of the excurrent duct. Here we evaluated the presence, localization and patterns of distribution of three hormone receptors, estrogen alpha (ERα), estrogen beta (ERβ) receptors and progesterone receptors (PR) along the excurrent duct of sexually matured male greater cane rats. Immunohistochemistry revealed presence of ERα in epididymal stroma but not epithelium, selective ERβ staining in narrow & apical cells as well as unique presence of PR in caudal epididymis, which to the best of our knowledge, is the first report on the cellular localization of progesterone receptor in the cauda epididymis. The result suggests the possible involvement of not only estrogen but also progesterone in the modulation of epididymal function in greater cane rat.