The smooth muscle of the ductus deferens is arranged as a thick outer longitudinal layer (SM(L)), a thick middle circular layer (SM(C)), and a thinner inner longitudinal layer (SM(L)). Between the epithelium and the inner longitudinal smooth muscle layer there is a moderately thick cellular layer of loose connective tissue, the lamina propria (LP). The connective tissue immediately surrounding the ductus deferens contains nerves and some of the smaller blood vessels that supply the duct. In fact, some of these vessels can be seen penetrating the outer longitudinal smooth muscle layer (asterisks).
SPERMATIC CORD AND DUCTUS DEFERENS KEY BV, blood vessels CT, connective tissue L, lumen of ductus deferens LP, lamina propria Lu, lumen of blood vessel N, nerve SM(C), circular layer of smooth muscle SM(L), longitudinal layer of smooth muscle arrowheads, stereocilia arrows, basal cell nucleus asterisks, small arteries supplying ductus deferens
Ductus deferens, human, H&E 320; inset 250.
The epithelial lining of the ductus deferens consists of pseudostratified columnar epithelium with stereocilia (arrowheads). It resembles the epithelium of the epididymis, but the cells are not as tall. The elongated nuclei of the columnar cells are read ily distinguished from the spherical nuclei of the basal cells (arrows). The epithelium rests on a loose connective tissue that extends to the smooth muscle; no submucosa is described.
A unique feature of the spermatic cord is the presence of a plexus of atypical veins (pampiniform plexus) that arise from the spermatic veins.
These vessels receive the blood from the testis. (The pampiniform plexus also receives tributaries from the epididymis.) The plexus is an anastomosing vascular network that constitutes the bulk of the spermatic cord. Portions of several of these veins (BV) are evident in the upper right of  figure above along with a number of nerves (N). The unusual feature of the veins is their thick muscular wall that, at a glance, gives the appearance of an artery rather than a vein. Careful examination of these vessels (inset) shows that the bulk of the vessel wall is composed of two layers of smooth muscle—an outer circular layer SM(C) and an inner longitudinal layer SM(L).
The prostate gland is the largest accessory sex gland. It consists of 30 to 50 tubuloalveolar glands that surround the proximal urethra. Because of this relationship, a common condition in later life, benign prostatic hyperplasia, can result in partial or total obstruction of the urethra. The prostatic glands are arranged in three concentric layers: a mucosal layer, a submucosal layer, and a peripheral layer containing the main prostatic glands. The mucosal glands secrete directly into the urethra; the other two sets of glands deliver their secretions through ducts that open into the prostatic sinuses on the posterior wall of the urethra. All of the glands are made up of a pseudostratified columnar epithe-lium that secretes several components of the semen, including acid phosphatase, citric acid (a nutrient for sperm), and fibrinolysin (which keeps the semen liquified). Aggregations of dead epithelial cells and precipitated secretory products form prostatic concretions in the alveoli of the glands; these are a characteristic feature that aids in recognition of the prostate. The stroma is characterized by numerous small bundles of smooth muscle, so that it can also be described as a fbromuscular stroma. Contraction of this muscle occurs at ejaculation, forcing the secretion into the urethra. Surrounding the gland is a fibroelastic capsule that also contains small bundles of smooth muscle.
Prostate gland, human H&E 47.