Enzyme histochemical studies of human spermatozoa correlated with the spermiogram

The activities of NADH2-diaphorase, leucine aminopeptidase, and acid phosphatase were studied histochemically in spermatozoa and seminal plasma of 28 ejaculates from 13 men with proven fertility and in 31 ejaculates from 29 men living in infertile marriages. The enzyme activities were correlated with the spermiogram. The NADH2-diaphorase activity was located exclusively in the midpiece of the spermatozoa, while the activities of leucine aminopeptidase and acid phosphatase seemed to be located only on the surface. A positive correlation was found between the NADH2-diaphorase activity and the spermatozoal motility, density, and morphology.