MORPHOMETRIC AND IMMUNOCYTOCHEMICAL STUDY OF THE FETAL, INFANT, AND ADULT HUMAN VAS-DEFERENS

The human vas deferens (VD) is often considered simply as a conduit to transfer mature sperm from the epididymis to the ejaculatory duct. Th e cells that make up the epithelium of the VD, however, exhibit many c haracteristics of cells found in more complex epithelia, which are inv olved in absorption and/or secretion. In the present investigation, mo rphometry was utilized to characterize in detail the changes incurred by the human VD during its development, growth, and aging and to deter mine if these changes correlate with testicular maturation. In additio n, the specific types of keratins present in the epithelial cells were defined, as well as desmin distribution in the muscular layers, durin g the various phases of the development, growth, and involution of the human VD. Results of the morphometric study are consistent with the i nterpretation that the development, growth, and aging of the VD are de layed, but parallel to, the identical phases exhibited by the human te stis. Further, a differential expression of distinct keratin types was observed in the VD during the various phases examined in this study. Taken together, these two correlations may suggest that the VD is unli kely to function solely as a conduit for sperm. The rationale for this interpretation is as follows: 1) the complex developmental and matura tional changes measured in the present investigation in the human VD a re common to other absorptive and/or secretory epithelia; and 2) these changes parallel developmental changes observed in other androgen-dep endent epithelia of the male reproductive tract, which also function t o contribute components to seminal fluid as well as to provide a condu it for sperm.