Adenosine triphosphate and motility characteristics of fresh and cryopreserved human spermatozoa

The concentration of ATP and the motility of human spermatozoa was measured in fresh and cryopreserved cells from the same 15 ejaculates. No coherent picture of the relationship between motility and ATP concentration emerged in whole semen or in spermatozoa washed by repeated centrifugation and resuspension in Biggers Whitten and Whttingham medium. This may have been due to the presence of dead spermatozoa and contaminating cells. After preparation on a Percoll gradient, the ATP concentration in fresh and cryopreserved spermatozoa was the same (6±0.7 nmol/10⁸ spermatozoa) but 85±2.5% of the fresh spermatozoa were progressively motile with an average path velocity of 55±3.5 pm/s compared to corresponding values of 33±5.3% and 44±3.4 μm/s in frozen/thawed spermatozoa. This suggests that the poor motility of cryopreserved spermatozoa does not result from deficient ATP production. No relationship was found between ATP concentration and the ability of motile spermatozoa in the ejaculate to survive freezing.