Seminal Vesicle


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Related to Seminal Vesicle: bulbourethral gland, seminal vesicle cyst

seminal vesicle

[′sem·ən·əl ′ves·i·kəl]
(anatomy)
A saclike, glandular diverticulum on each ductus deferens in male vertebrates; it is united with the excretory duct and serves for temporary storage of semen.

Seminal Vesicle

 

in male salientians and birds and in some male fish and mammals (including man), a glandular widening or protrusion of the terminal portion of the seminal duct that releases an alkaline mucosal secretion needed to nourish and mobilize spermatozoa. In most animals the secretion of the seminal vesicles is a component of semen that serves to liquefy sperm and, in some animals, promotes the formation of sper-matophores from sperm.

Seminal vesicles are paired or unpaired. They are formed during embryonic development from various portions of the deferent ducts and may be simple widenings or sacculated processes of the ducts. In some animals seminal vesicles are independent structures united to the deferent ducts only by a narrow canal. Seminal vesicles are especially developed in some rodents and insectivores; they are absent in monotremes, marsupials and many predatory animals.

In man, the seminal vesicles form a paired organ 4–5 cm long, 2 cm wide, and 1.0–1.5 cm thick. They are located in connective tissue between the posteroinferior surface of the urinary bladder and the rectum, adjacent to the base of the prostate. The vesicles are convoluted tubes with numerous recesses. The vesicular wall consists of an external connective-tissue membrane, a weakly developed muscular membrane, a submucosal layer, and a mucous membrane with columnar or cubical epithelium. The excretory duct of the seminal vesicles is connected to the terminal portion of the seminal canal, forming the ejaculatory duct.

References in periodicals archive ?
In the extreme anterior of the seminal vesicle (cephalic direction) next to the prostate gland, there is variation in the organization of the euspermatozoa and the paraspermatozoa.
DHT is responsible for the proliferative action on prostate and seminal vesicles (Kashiwagi et al.
Fructose serves as a marker for the seminal vesicles and enzymes are markers for the prostate gland (acid phosphatase) and the epididymis ([alpha] glucosidase).
Cysts of seminal vesicle usually become apparent during second to third decade of life, perhaps related to onset of sexual activity at this age(1).
Effects of testosterone on messenger ribonucleic acid and protein synthesis in rat seminal vesicle.
Dynamic contrast enhancing helps in the detection of cancer and for the assessment of extra-capsular extension, distal urethral sphincter and seminal vesicles involvement.
Noteworthy, various cases have also been validated in other sites, including the pancreas, urinary bladder, and seminal vesicles (8-10).
2005) and secretory activity by the prostate and seminal vesicles therefore is a sensitive, androgen dependent function (Veneziale et al.
Intravenous urography may show a smooth indentation on the urinary bladder from mass effect of the enlarged seminal vesicle.
The histogenesis of seminal vesicle paraganglioma is unknown.
CT scan of the patient confirmed agenesis of left kidney with associated ipsilateral seminal vesicle cyst.