Where does sperm come from? 1. Testis is the "birthplace" of sperm. There are mainly three kinds of cells in human testis: sertoli cells, interstitial cells and germ cells. Sertoli cells and germ cells constitute seminiferous epithelium, while interstitial cells exist between seminiferous tubules. Sertoli cell is a kind of high columnar cell embedded with spermatogenic cells at all levels. In the past, people thought that the main function of sertoli cells was to provide support and nutrition for spermatogenic cells, so they were called sertoli cells. In fact, supporting cells have a great role. They are connected together to form a barrier, making seminiferous tubules a closed microenvironment.

Where does sperm come from? 2. Sertoli cells of rats can secrete androgen binding protein, which has strong binding force with testosterone. It can concentrate the testosterone synthesized and secreted by interstitial cells, so that the testosterone concentration in the tube is 100 times higher than that in plasma, which is necessary for spermatogenesis. It is not clear whether human testis has the same androgen binding protein.

Where does sperm come from? 3. Sperm cells become more and more mature from the bottom to the top of supporting cells. Spermatogonial cells are distributed at the bottom, followed by primary spermatocytes, secondary spermatocytes and spermatocytes. A spermatogonia can form 256 spermatocytes with only half chromosomes after many mitoses and two mature divisions (meiosis), of which 50% contain X chromosomes and the other 50% contain Y chromosomes. Spermatogonia and spermatocytes are round and tailless, and the tail gradually appears in spermatocytes. Sperm cells undergo a series of changes, and finally mature into tadpole-shaped sperm, which is discharged into seminiferous tubules.

The maturation time of sperm in seminiferous tubules is about 64-72 days. In addition, it will take 19-25 days to further mature in epididymis, and then sperm will have mobility and fertilization ability. Therefore, the whole process of sperm maturation takes about 90 days. This is why drugs should be used to treat azoospermia and oligospermia for at least 3 months. So don't be impatient. After taking the medicine for a few days, I saw that the number and activity rate of sperm had not changed, so I immediately became depressed and changed to another medicine. In the end, all kinds of drugs were tried, but they didn't work.