Sperm after leaving the nucleus are not yet fully mature. In the epididymis undergo a series of morphological changes , biochemical and functional . Their effect is to achieve the ability of sperm to the progressive movement , survival in male and female genital tract , capacitation , acrosome reaction and carrying out fertilization of the ovum . The specific environment in which the spermatozoa mature and are maintained viability , is produced by the epithelial cells lining the duct of the epididymis . These cells synthesize and release into the lumen of proteins, glycoproteins , glycolipids , phospholipids, needed at each stage of ripening and storage of sperm. Secretory processes , and resorbcyjne epithelial cells are mainly regulated by androgens . Rat epididymal epithelial cells exhibit characteristics of steroidogenic cells , in vitro synthesized androgens that are flavored by the cells to 17b -estradiol . Epididymal epithelial cells are a source of still other hormones, such as Proopiomelanocortin , proenkefalina or oxytocin . Therefore, you should also consider the epididymis as peripheral endocrine gland .