[The effect of high concentration of sodium and potassium ion on motility of human sperm preserved in electrolyte-free solution].

Purpose: To assess the effect of high concentration of sodium and potassium ion on the motilities of human sperm following the preservation in electrolyte-free solution.

Patient: Semen samples were obtained from patients attending our infertility clinic. The motilities of their sperm were more than 40%.

Method: Ejaculated sperm were washed by using the electrolyte-free Percoll gradient and then preserved in electrolyte-free solution at 4 degrees C for a week. The preserved sperm was incubated and analyzed after the addition of electrolyte solutions under acid or alkaline condition. The sperm were continuously preserved for a day at room temperature and analyzed.

Result: The sperm was by the addition of 35-135 mM Na+ or 5-135 mM K+ in acid solutions. Under the alkaline conditions, sperm were reactivated without Na+ or K+. However, the addition of 135 mM Na+ or K+ significantly decreased in sperm motilities. The some sperm in the solution containing low concentration of Na+ or K+ ions maintained their motilities for a day at room temperature. However, all sperm lost their motilities in the 135 mM Na+ or K+ solutions.

Conclusion: The high concentration of Na+ or K+ ions had detrimental effects on motilities of sperm following the preservation in electrolyte-free solution.