Prostate

The Prostate gland is a large accessory gland consisting of 30-50 tubuloalveolar glands embedded in a fibromuscular stroma. It surrounds the proximal urethra. Glands are arranged in three concentric layers; the inner mucosal layer (which contains mucosal glands secreting directly into the urethra), the intermediate submucosal layer (which contains submucosal glands that has ducts into the prostatic sinuses), and the peripheral layer (which contains the main prostatic glands, also opening into the prostatic sinuses). The prostate secretes the following enzymes:

• Prostate acid phosphatase (PAP) presents in large amounts in lysosomes of epithelial cells. Blood levels of PAP are used to detect prostate cancer, and it has a potential role in fertilization.
• Fibrinolysin liquifies semen
• Prostate-specific antigen (PSA) is a serine protease (also liquifies semen). Liver of normal individuals produces a small amount in the blood. A normal prostate also releases a small amount of prostate secretion. High levels in the blood indicates blood.

Secretions are pumped into the urethra during ejaculation. The prostatic alveoli in older men contain prostatic concretions (corpora amylacea) and “starchy bodies”. The latter are varied in size and shape (up to 2mm) and appear as concentric lamellated bodies. They are formed from precipitation of secretory material around cell debris (may be partially calcified).