Provocation testing of human sperm motility using energy substrates and activators of the cyclic nucleotide system. I. Establishment of conditions for response testing.

In order to establish a series of provocation tests to evaluate the integrity of the sperm cAMP pathway, manganese (Mn), 2-deoxyadenosine (DEA) (via adenylyl cyclase), and methyl-isobutyl-xanthine (MIX) (via phosphodiesterase) were tested for their capacity to activate the progressive motility of human sperm. Optimal responses were obtained using washed sperm previously incubated for 3 hours in substrate-poor medium (Hepes-buffered saline). Longer periods of incubation required the presence in addition of an energy substrate such as glucose. Exposure of sperm to seminal plasma for 24 hours prior to washing attenuated the responsiveness of the sperm to the different activators. Preliminary studies on the activation of the progressive motility of washed sperm from four normozoospermic men under fertility investigation, prepared under identical conditions, revealed differences in the pattern of response which may have pathophysiological relevance.