This name is controversial. The seminal glands do not store semen, they instead produce a significant proportion of the seminal fluid. Therefore, 'seminal vesicle' is an inaccurate term for the function of the organ, but is frequently used in the literature. I prefer seminal gland as it is a more accurate description of what the glands actually do.
Structure and Relations
The seminal glands are paired structures, about 5 cm in length. They lie posterior to the bladder, anterior to the rectum and supero-posterior to the prostate gland. The terminal part of the ductus deferens passes medial to the gland. The peritoneum lies along the most superior part, and the glands are anterior to the rectovesical fascia. The glands are closely related near the prostate, but diverge as they pass superiorly.
The gland is a long, coiled tube with short sacs branching off the side, about 15 cm long if uncoiled. When coiled, the gland is slightly larger posteriorly and narrows near the prostate, where it communicates with the ampulla of the ductus deferens to form the ejaculatory duct. The gland is surrounded by a fibrous capsule.
Microscopic Features
The epithelium of the seminal glands is cuboidal. The mucosa is coated by two layers of smooth muscle and then a surrounding connective tissue capsule.
Function
The seminal glands produce a component of the semen, which is added to the sperm and prostatic secretions to form the final product. The gland produces about 85% of the seminal fluid.
