The Metabolic Activity of the Bovine Epididymis

III. CHOLESTEROL AND ESTERIFIED CHOLESTEROL METABOLISM Department of Animal Science, University of Georgia College of Agriculture, Athens, Georgia 30602, U.S.A. (Received 22nd August 1974) The maturation process which spermatozoa undergo in the epididymis may be partly attributed to a synthesis in vivo of products used in this maturation (Turner & Johnson, 1973a). Scott, Wales, Wallace & White (1963) reported that glycerylphosphorylcholine (GPC) synthesis occurred in the caput and cauda epididymidis of the rabbit both in vivo and in vitro. Hamilton, Jones & Fawcett (1969) reported synthesis in vitro of cholesterol from acetate in the mouse epididymis and ductus deferens. Hamilton & Fawcett (1970), utilizing the rat epididymis and ductus deferens, showed synthesis in vitro of cholesterol and testosterone from acetate. Turner & Johnson (1971) reported that, with the removal of spermatozoa from an area of the epididymis, lipid fractions tended to increase in concentration and free cholesterol as a percentage