Sertoli syncytium is one of the most famous and significant forms of testicular structure in mammals. It is determined by the presence of a well-developed syncytial layer of cells around the median gland. The average size is approximately 20x20 microns. Cells can be small or large, oval or polygonal. They are differentiated into two types: internal and external. The inner one contains the core and fatty inclusions. There are oval joints on the surface of the layer. Arteries and nerves penetrate into the syncytial layer, and tubules with unstable sinusoidally curved basement membranes and lattice-shaped clearings penetrate into the inner zone. Not the entire layer participates in spermatogenesis, but only its internal peritubular section with the median glands. First, mature male reproductive cells pass through it, then female ones. Sertoli syncytia are found not only in the seminiferous tubules, but also in the white matter cells. From them a very important male sex gland is formed - the hair follicle. She does not need testicular hormones; they are required for other glands: the pituitary gland, the thyroid gland, the parathyroid and parafollicular glands. All stages of spermatogenesis take place in the perivascular interstitial layer of cells with an externally ordered arrangement. However, judging by their shape and location, this is a syncytium. The topology of the interstitium changes with aging: the epididymis has an external peritubular, internal pericytal, intermediate interstitial layers and the epididymal cord itself. The spermatogenic epithelium is gradually replaced by a transparent stroma with lymphoid cells and centers of follicular formations. They occur mainly in young men. With age, the cord itself becomes thinner, and the density of porphyrocytes decreases. Everywhere the mitotic zone is replaced by fibrous connective tissue. In children, the average diameter of the organ varies from 0.9 mm to 5.7 mm, in men – 3.0-5.7 cm. The shorter the cord, the higher the risk of obstruction and hypoplasia. The optimal condition is if it covers the entire length of the seed