The prostate consists of four distinct glandular regions where the peripheral zone comprises 70% and the central zone 25% of the prostate mass. The glandular component of prostate is composed of ducts and acini, which are morphologically identical and both appear to function as dispensable reservoirs.
The prostatic glands are lined by a pseudostratified columnar epithelium with secretory cells. As with other glandular organs, the secretory cells throughout the prostate are separated from the basement membrane and stroma by a layer of basal cells.
The non-glandular components of the prostate include the pre-prostatic sphincter, fibromuscular stroma, capsule and also supplying blood vessels and nerves. The fibromuscular stroma is composed of bundles of smooth muscle cells that are arranged by bands of dense fibrous tissue.
The function of the prostate is to produce one third of the fluid that makes up semen. Together with sperm and fluid from seminal vesicles, the prostatic fluid contributes to the semen composition. The fluid produced is a protective and nourishing vehicle for sperm cells. Prostatic secretion consists of lipids, proteolytic enzymes, acid phosphatase, fibrinolysin and citric acids. The seminal vesicles are located behind the prostate and insert into the prostatic gland to secrete seminal vesicle fluids into the urethra.