The Role of Adenine Nucleotides and the Effect of Caffeine and Dibutyryl Cyclic AMP on the Metabolism of Guinea Pig Epididymal Spermatozoa

High levels of adenine nucleotides are present in sperm taken from the caput segment of the guinea pig epididymis. This level declines progressively in the corpus and cauda segments where there is also a progressive increase in in vitro glycolysis. Nucleotide control of glycolysis is suggested by the observation that the depletion of nucleotide pools by incubation in the absence of substrate leads to increased glycolytic rates. This is particularly pronounced in caput sperm. Sperm motility in different segments, however, is not enhanced by lowering nucleotide levels in this manner.