Prostrate

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The prostate (from Greek π"οστάτης - prostates, literally "one who stands before", "protector", "guardian") is a compound tubuloalveolar exocrine gland of the male mammalian reproductive system. Women do not have a prostate gland, although women do have microscopic paraurethral Skene's glands connected to the distal third of the urethra in the prevaginal space that are homologous to the prostate.

Function

The main function of the prostate is to store and secrete a clear, slightly alkaline (pH 7.29) fluid that constitutes 10-30% of the volume of the seminal fluid that, along with spermatozoa, constitutes semen. The rest of the seminal fluid is produced by the two seminal vesicles. The alkalinity of seminal fluid helps neutralize the acidity of the vaginal tract, prolonging the lifespan of sperm.

The prostate also contains some smooth muscles that help expel semen during ejaculation.

Regulation

To work properly, the prostate needs male hormones (androgens), which are responsible for male sex characteristics.

The main male hormone is testosterone, which is produced mainly by the testicles. Some male hormones are produced in small amounts by the adrenal glands. However, it is dihydrotestosterone that regulates the prostate.

Development

The prostatic part of the urethra develops from the pelvic (middle) part of the urogenital sinus (endodermal origin). Endodermal outgrowths arise from the prostatic part of the urethra and grow into the surrounding mesenchyme. The glandular epithelium of the prostate differentiates from these endodermal cells, and the associated mesenchyme differentiates into the dense stroma and the smooth muscle of the prostate. [2]The prostate glands represent the modified wall of the proximal portion of the male urethra and arises by the 9th week of embryonic life in the development of the reproductive system. Condensation of mesenchyme, urethra and Wolffian ducts gives rise to the adult prostate gland, a composite organ made up of several glandular and non-glandular components tightly fused within a common capsule.

Skene's glands found in many females are homologous to the prostate gland in males.

"In 2002, what was once an obscure female anatomical feature known as the paraurethral glands, or Skene's glands, was officially renamed the prostate by the Federative International Committee on Anatomical Terminology."

Structure

A healthy human prostate is slightly larger than a walnut. It surrounds the urethra just below the urinary bladder and can be felt during a rectal exam.

The ducts are lined with transitional epithelium.

Within the prostate, the urethra coming from the bladder is called the prostatic urethra and merges with the two ejaculatory ducts. (The male urethra has two functions: to carry urine from the bladder during urination and to carry semen during ejaculation.) The prostate is sheathed in the muscles of the pelvic floor, which contract during the ejaculatory process.

See also [ Prostate massage ]


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