[Morphology and zonal division of the ductus epididymidis of rats. I. Investigation of semithin-sections (author's transl)].

The ductus epididymidis of adult rats can be subdivided in 9 zones. All zones consist of principal cells (pc), basal cells and granular and agranular leucocytes. However, dependent on the zone the length of the microvilli, basophilia of the Golgi region and the size and number of vacuoles and granules of the pc show differences. In addition, apical and bottle-shaped (narrow cells) occur in zone 1 and 2 and basal clear cells in zone 2-4. Furthermore, 4 types of clear cells (cc) can be distinguished which differ in number, size and staining properties of their granules; cc with light granules (type I) exist in zone 5 and cc with dark granules (type II) predominate in zone 6 whereas cc with a mixed granule type (type III) occur especially in zone 7 and cc with grey granules (type IV) are limited to zone 8 and 9. Beside the different structure and distribution of the epithelial cells the diameter of the duct lumen and the height of the epithelium differ in the course of the ductus epididymidis.