Maturation, transport, and fate of spermatozoa in the epididymis.
The most recent evidence relating to maturation of fertilizing ability, transport, and fate of sperm in the epididymis is presented. In the mammals examined, the ability to fertilize is acquired as spermatozoa pass through the duct to the cauda region. A few studies indicate that spermatozoa are transported passively through the proximal part of the epididymis to the cauda region by mild autonomous peristaltic contraction of the duct wall. The fertilizing ability of spermatozoa in the cauda and vas deferens disappears within a few days after bilateral orchiectomy and is quickly lost after transfer of the epididymis to the higher ambient temperature of the abdominal cavity. Conflicting evidence prohibits a general statement as to the fate of spermatozoa that enter the normal epididymis in the sexually rested male.