Postnatal development of epididymis and ductus deferens in the rat

Abstract

The postnatal maturation of regions of the epididymis and intragonadal segment of the deferens duct was studied in the rat by light- and transmission electron microscopy. Maturation of the genital duct starts in the distal cauda epididymidis and ductus deferens after one week of life, and one week later, in the more cranial segments of the epididymis. Epithelial principal cells and peritubular contractile cells are structurally mature 35 days after birth. The synchronous changes of these cells indicate that the same factors control their postnatal maturation. The epithelial principal cells obtain an endocytotic apparatus and long stereocilia, whereas peritubular cells acquire contractile features. These changes are associated with a progressive increase in the immunoreaction for smooth muscle actin in both cell types. Smooth muscle myosin is detected in the apical region of the epithelial cells and the peritubular cell cytoplasm by day one of postnatal development. The differentiation of contractile cells in the wall is accompanied by progressive organization of the pericellular matrix into a continuous basement membrane. Although fibronectin is visible at birth, it is gradually removed from the tubule wall.

Plasticity of basal cells during postnatal development in the rat epididymis

“…In addition, we observed no migratory KRT5-positive cells crossing the basement membrane into the VD and epididymal epithelia, a typical phenomenon for cells coming from the circulation such as dendritic cells and macrophages. We, therefore, propose that basal cells arise from the differentiation of the primitive columnar epithelial cells, as has also been suggested in other studies (Martan 1969, Sun & Flickinger 1979, 1982, Francavilla et al 1987). …”

“…The epididymis of several species including humans and rodents is immature at birth and epithelial cells acquire their differentiated phenotypes over an extended postnatal period (Nilnophakoon 1978, Sun & Flickinger 1979, Zondek & Zondek 1980, Francavilla et al 1987, De Miguel et al 1998, Rodriguez et al 2002, Marty et al 2003). Based on morphological studies, the postnatal development of the rat epididymis has been divided into three phases, namely an undifferentiated period (days 1–15), a differentiation period (days 16–44), and a period of expansion (days beyond 44) (Sun & Flickinger 1979).…”

Developmental expression of immobilin in the rat epididymis

“…The ultrastructural features of the predominant epithelial cell type, i.e., the principal cell, lining the epididymis of rats ranging in age from birth to postnatal day 90 have been studied by several investigators (Sun and Flickinger, 1979;Francavilla et al, 1987;Hermo et al, 1992a). Up to postnatal day 21, these cells have a uniform appearance along the length of the epididymis and show features of structurally undifferentiated cells; they are referred to as undifferentiated columnar epithelial cells.…”

High‐resolution imaging of the actin cytoskeleton and epithelial sodium channel, CFTR, and aquaporin‐9 localization in the vas deferens

“…Our high-resolution confocal microscopy images showed well preserved and complete images of stereocilia bundles of individual cells (Figures 4, 5, and 9). Previous studies on the histology of the vas deferens using either histochemical staining or electron microscopic ultrastructure showed mostly cut and scattered stereocilia, for example, Francavilla et al (1987) and Khadijah Ramli et al (2018Ramli et al ( , 2019 that do not represent the dense organization and the structure of the actin bundles.…”

“…Histological studies have shown that the apical borders of the epithelial cells in the vas deferens are covered by microvilli or stereocilia (Francavilla et al, 1987;Hamilton & Cooper, 1978;Höfer & Drenckhahn, 1996;Rodriguez & Bustos-Obregón, 1993). Both microvilli and stereocilia are cell projections that have backbones composed of actin filament bundles (Pelaseyed & Bretscher, 2018).…”