Leydig's interstitial cells and hormonal regulation
Between the seminal canals lie Leydig's interstitial cells. These are endocrine cells that mainly produce testosterone, the male sexual hormone, and release it into the blood and into the neighboring tissues. An initial active stage of these cells occurs during the embryonic development of the testis. Later in juvenile life, due to the influence of the LH (luteinizing hormone) secreted by the anterior hypophysis (pituitary gland), Leydig's interstitial cells enter a second, long lasting stage of activity. Together with the hormones secreted by the adrenal cortex, testosterone initiates puberty and thus the maturation of the sperm cells.