Accessory sex gland function in normal young (20-25 years) and middle-aged (50-55 years) men.

A comparison of various parameters of prostatic and vesicular secretory function was made between the seminal plasma of young (20-25 years; n = 23) and middle-aged (50-55 years; n = 19) male volunteers. These parameters included prostatic acid phosphatase, zinc, citric acid, spermine, spermidine, putrescine (prostatic origin), fructose, and prostaglandin E (vesicular origin), in addition to protein and testosterone. Spermatozoa were counted and monitored for abnormalities. The concentration in the ejaculate of the majority of the parameters investigated did not change with age, although the total contribution to the ejaculate from the prostate and seminal vesicles was reduced significantly in the older men. The concentration of three constituents was significantly altered in the older age group: putrescine (P less than 0.001) and prostaglandin E (P less than 0.01) were reduced, while zinc levels were elevated (P less than 0.05). These changes are discussed in relation to possible disturbances of prostate function and pathology in the middle-aged man.