Biology of the scrotum. II. Suppression by abdominal temperature of transepithelial ion and water transport in the cauda epididymidis.

Spermatozoa of scrotal mammals will mature in, but cannot be stored at abdominal temperatures in the epididymis reflected to the abdomen. Whether the failure of sperm storage at abdominal temperatures reflects a temperature sensitivity of the caudal epithelium, or of the spermatozoa, is unknown. Microperfusion of the lumen of the cauda epididymis revealed that abdominal temperature soon brings a significant change in the transepithelial transport of water, Na+, K+ and Cl-, and in the Na+ and K+ levels in the luminal fluids in the cauda. Thus, the cauda epididymis, as well as the testis, behaves as a temperature-dependent organ.