[Effects on the mouse epididymis of juvenile ligation of the ductuli efferentes or proximal epididymal duct: qualitative and quantitative histological studies (author's transl)].
The ductuli efferentes or the epididymal duct between the head and body were ligated in young mice aged 20-30 days, and effects of the ligation on the epididymis were histologically examined by means of qualitative and quantitative procedures at the age of 50-60 days. As reported previously (Takano, 1980), the epididymal duct of the mouse can be divided into five regions (regions I-V). On the morphometric basis, the five regions can be divided into two major portions, proximal and distal. The proximal portion consists of regions I, II and III which form the head of the epididymis. The distal portion is composed of regions IV and V which form the body and tail of the organ. The results of the qualitative and quantitative analysis in the previous study suggested that the proximal portion is functionally related with maturation of sperms and the distal portion is concerned with storage of sperms. Juvenile ligation of the ductuli efferentes or the epididymal duct between the proximal and distal portions caused the following changes in the epididymal duct. 1. Region I, "initial segment", was normally characterized by the lining of high columnar epithelial cells. Juvenile ligation of the ductuli efferentes impaired differentiation of region I, but not that of the remaining regions. Epididymal duct ligation between regions III and IV, on the other hand, exerted no influence on differentiation of the entire duct. Thus differentiation of region I is dependent upon the luminal contents transferred from the testis. 2. The luminal contents were stored in abundance in the distal portion after ligation of the ductuli efferentes, as were in the case of the normal control. On the other hand, the luminal contents were abundant in th proximal portion and scanty in the distal portion after epididymal duct ligation between the proximal and distal portions. These results suggest that the luminal contents may be produced in the proximal portion even after ligation of the ductuli efferentes, transported into the distal portion and stored there. 3. In region IV, the epithelium showed marked histological changes after ligation of the ductuli efferentes or the epididymal duct between regions III and IV. After ligation of the ductuli efferentes, PAS-positive granules and masses frequently appeared in the epithelial cells. After epididymal duct ligation between regions III and IV, clear vacuolated cells and large vacuole-like spaces frequently appeared within the epithelium. Thus it is likely that the epithelial cells of region IV are functionally related to the luminal contents stored.