LDH-C4 in human seminal plasma and testicular function. III. Relationship to other semen variables.

Lactic dehydrogenase C4 was analysed in human seminal plasma, expressed in nanokatals and related to the sperm count. The LDH-C4/sperm ratio has previously been shown to reflect the functional integrity of the seminiferous epithelium. In the present study this ratio was related to several other semen variables that reflect various functional or biochemical properties of the spermatozoa or other cell systems. For none of these variables was there a significant linear correlation with the LDH-C4/sperm ratio, but interesting differences became apparent when the semen samples were subdivided into two groups, those with normal (less than 20) and those with a high (greater than 20) ratio. For nuclear chromatin stability, oxygen consumption, succinate-induced increase in oxygen consumption and lipid peroxidation, there were significant differences between the two groups. There was no difference between the groups for the staining properties of the DNA-DNP complex, zinc, fructose and free 1-carnitine content in the ejaculate, and the zinc/fructose ratio. The results indicate that functional properties of the spermatozoa can be related to the status of the seminiferous epithelium.