Fig. 4. Removing epididymal decapacitation factors increases the sensitivity of wild-type sperm, but not GalT I-null sperm, to Ca²⁺ ionophore. Wild-type (gt +/+, A) and GalT I-null (gt –/–, B) sperm were isolated from the cauda epididymis by trituration and resuspended in fresh media, centrifuged and resuspended again (washed). Control sperm were triturated and centrifuged in parallel but resuspended in the original supernatant (unwashed). The sperm were then capacitated for varying periods of time before incubation with 10 µM A23187 or an equal volume of DMSO (data not shown). Each point represents the mean±s.e.m.; n=3 experiments. In a single experiment, the value of each data point represents three determinations for a total of nine individual assays. A minimum of 200 sperm was counted for each determination. *P<0.01.