Studies on the metabolism of semen. 9. Effect of surface active agents with special reference to the oxidation of succinate by spermatozoa.

In the course of investigations on the respiration and the cytochrome-succinic oxidase system ofram spermatozoa (Mann, 1945, 1951a, b; Humphrey & Mann, 1949) two phenomena have been observed: (i) it was found that as the result of freezing and subsequent thawing, or after prolonged storage of semen in vitro, there was a leakage of cytochrome c from the spermatozoa into the surrounding fluid; (ii) it was noticed that, whereas the oxygen consumption of suspensions of fresh, washed spermatozoa was but slightly increased by the addition of succinate, sperm cells which have become senescent or have undergone some damage with resulting lowered motility and respiration, responded to the addition of succinate by a markedly increased uptake of oxygen. We have now found that it is possible to produce the stimulating effect of succinate on the rate of sperm respiration, characteristic of senescent or damaged spermatozoa, by exposing the sperm cells to the action of certain ionic and non-ionic detergents. Under the influence of the surface-active agents, motility, fructolysis and respiration were suppressed, but it was possible to raise the rate of oxygen consumption of the detergent-treated sperm by the addition of sodium succinate.