THE EFFECT OF DILUTION ON THE CONCENTRATION OF SODIUM, POTASSIUM, CALCIUM AND MAGNESIUM IN RAM AND BULL SPERMATOZOA

Abstract

Summary. Mild dilution (<1·8) of ram and bull semen in isotonic sodium phosphate diluent of pH 7·0 caused an influx of sodium and an efflux of potassium, calcium and magnesium from the spermatozoa. Equilibrium was reached soon after dilution and little further change in the concentration of these cations was observed over 3 hr. Similar changes occurred when ram and bull semen was diluted in tris and veronal diluents of pH 7; however, calcium was found to accumulate in ram spermatozoa diluted in tris. Diluting semen in buffers of pH range 8·5 to 5·5 indicated that potassium loss from the spermatozoa increased with increasing pH. Greater dilution (1:100) and exhaustive washing (four times) had a similar but more severe effect on the cation concentration of ram and bull spermatozoa. A large influx of sodium was accompanied by a marked depletion of potassium which tended to be further depleted over 3 hr.