THE RÔLE OF OXYGEN IN THE METABOLISM AND MOTILITY OF HUMAN SPERMATOZOA

Abstract

It is demonstrated that human spermatozoa contain a virtually complete respiratory system, namely, succinic dehydrogenase, cytochromes B and C and cytochrome oxi-dase. However, the O2 consumption of these cells is negligi-ble in the absence of substrate or in the presence of glucose and cannot be interpreted as a true respiration. Na succinate is oxidised vigorously by the spermatozoa but any energy made available in this reaction is not coupled with motility since succinate alone will not support motility. In regard to the depressing effect of high O2 pressures on the motility of the spermatozoa, it is shown that the spermatozoa may produce enough H2O2 in the course of their aerobic metabolism to destroy motility. If dilute Hb or catalase is present when human spermatozoa are exposed to 95% O2 for several hrs. at 38[degree] C. no failure of motility will take place. Lastly, it is shown that the motility of the spermatozoa can be completely destroyed by the addition of small amts. of peroxide.