Prostate gland

Prostate gland, male reproductive gland that surrounds the urethra at the base of the urinary bladder and that secretes prostatic fluid. This organ is formed of fibrous muscular and glandular tissue. It is described as having the shape of a chestnut and as being an inverted pyramid whose base is applied to the neck of the bladder. The normal gland usually measures about 1 in (2.54 cm) from front to back, 1 1/4 in (3.18 cm) from above downward and nearly 2 in (5 cm) from side to side. The connective tissue around the gland is condensed to form a fibrous capsule. There is a groove between the neck of the bladder and the base of the prostate that contains a venous plexus. The prostate is traversed from top to bottom by the urethra. The glandulary tissue consists of secretory acini. After middle age, acini may contain concretions of secretion and desquamated cells.

The glands of the median lobe and mucosal glands constitute the glands of the inner zone, in which penile enlargement usually starts. Cancer of the prostate usually starts in the outer zone which consists of the main prostatic gland.

See also: Reproduction.