Where is the seminal vesicle located and what is its function?

I believe every man is familiar with the seminal vesicle. Normal men have seminal vesicles, but many men cannot tell where the seminal vesicles are located if you ask them. So let me introduce it to you below.

Location of the seminal vesicle

The seminal vesicle, also known as the seminal vesicle gland, is an oblong cystic organ located above and behind the prostate gland and behind the bladder base, on the outer side of the vas deferens fossa, one on each side, with an uneven surface, about 4-6 cm long, 1.5-2.0 cm in diameter, and a capacity of 2-4 ml. It is a spindle cone-shaped cyst that is flat front to back. The lower end of the seminal vesicle is a thin straight excretory duct that merges with the end of the vas deferens fossa to form the ejaculatory duct. The ejaculatory duct is about 2 cm long, penetrates the prostate from the prostate base, opens on the spermatic condyle, and is also the channel for transporting semen. Under the stimulation of androgens. The seminal vesicle secretes a weakly alkaline light yellow liquid containing fructose, prostaglandins and other ingredients. Fructose provides energy for the movement of sperm. Since the seminal vesicle and the vas deferens have the same embryonic origin, congenital absence of the vas deferens is accompanied by absence of the seminal vesicle. This can be used to distinguish azoospermia (complete lack of sperm) due to testicular abnormalities from azoospermia due to congenital absence of both vas deferens. In the latter case, the semen contains no fructose and only a small amount of citric acid in the seminal vesicle secretion fluid.

Function of the seminal vesicle

In the past, it was mistakenly believed that the seminal vesicle was an organ that stored sperm. Now it is understood that the seminal vesicle is a duct gland, one of the male accessory glands. The seminal vesicle secretes only during ejaculation, and its secretion is the main source of seminal plasma. It is mixed with the secretions of the prostate, the bulbourethral glands, and the sperm stored in the tail of the epididymis and the vas deferens to form semen. The seminal vesicle secretion is alkaline, a light yellow liquid, containing fructose, prostaglandins, and coagulase. Semen segmentation studies have shown that the last part of the semen ejaculated is the secretion of the seminal vesicle and a small amount of sperm. Compared with other parts of the semen, these sperm are immobile or move very little, and are often of low quality. The sperm in the seminal vesicle is because the semen flows into the seminal vesicle during the sexual quiescence period. The longer the sexual quiescence period, the more sperm are stored in the seminal vesicle. Because the seminal vesicle fluid is the last to be ejaculated, it actually plays the role of flushing out the sperm in the urethra. The fructose content in the seminal vesicle secretions is very high, which is the energy source for the movement of sperm after they are discharged from the body. In the past, prostaglandins in semen were believed to come from prostate secretions, and thus were mistakenly named "prostaglandins". Now it has been proven that they come from the seminal vesicles. There are several types of prostaglandins in the seminal vesicle secretions. Some relax the cervix, while others can enhance sperm movement and the ability to pass through cervical mucus and increase fertilization rates. The coagulase in the secretions can temporarily coagulate the semen after ejaculation to limit sperm activity, save energy and facilitate fertilization.