It has been suggested that a-glucosidase may be a marker of epididymal patency and function. Spermatozoal ATP concentrations decrease during passage through the epididymis, indicating efficient maturation. We correlated sperm motility with seminal plasma a-glucosidase activity and spermatozoal ATP. The sperm motility correlation with a-glucosidase activity was significantly positive, and the sperm motility correlation with spermatozoal ATP was significantly negative. It appears that high-aglucosidase activity and low-spermatozoa1 ATP were present in semen with good sperm motility and could possibly indicate efficient epididymal function.

Good sperm motility in normozoospermic men was associated with high bound and total sialic acid (SA) and pyruvate concentrations in the seminal plasma, as well as high endogenous (sperm) pyruvate concentrations. The presence of sialidase in the seminal plasma was also demonstrated for the first time. The results suggest that SA is metabolized to pyruvate by a N-acetylneuraminic acid (NANA)-aldolase in the seminal plasma and that pyruvate subsequently serves as an energy source for sperm.

The ability of the markers alpha-glucosidase, carnitine, and glycerylphosphorylcholine to indicate epididymal obstruction was studied. alpha-Glucosidase was found to be the best discriminant, with 93.4% correct classifications. The possible interrelationship between alpha-glucosidase activity, sperm ATP, and epididymal function was then studied. alpha-Glucosidase correlated positively with the percentage of motile sperm (p = 0.0212) and with the percentage of sperm with good forward progression (p = 0.0374), but correlated negatively with the sperm ATP (p < 0.0500). It was concluded that lower ATP and higher alpha-Glucosidase may be markers of efficient epididymal function. The possible epididymal origin of detached ciliary tufts (DCTs) was studied by determining ATP and alpha-glucosidase activity in patients with DCTs. The mean ATP in patients with DCTs was significantly higher (p = 0.009), but the alpha-glucosidase activity significantly lower (p = 0.0412) than in the control group. These results seem to support the epididymal origin of DCTs.