Na+, K+-ATPase and Ca2+, Mg2+-ATPase activity in spermatozoa of infertile men with different forms of pathospermia

Abstract

Ion-exchanging ATPases play an essential role in biology of spermatozoa, inclu­ding their motility, hyperactivation, chemotaxis, acrosome reaction etc. The aim of present study was to analyze Na + , K + -ATPase and Ca 2+ , Mg 2+ -ATPase activities in spermatozoa of the infertile men with different forms of pathospermia and to explore a possible role that they may play in male infertility. A significant reduction in ouabain-sensitive Na + , K + -ATPase activity in sperm cells of infertile men with oligozoo-, asthenozoo-, oligoasthenozoo- and leucocytospermia was shown. The results show that asthenozoo-, oligoasthenozoo- and leucocytospermic patients have significantly impaired thapsigargin-sensitive and thapsigargin-insensitive Ca 2 + , Mg 2+ -ATPase activity compared to healthy men. However, Ca 2+ , Mg 2+ -ATPase activity has a tendency to increase in patients with oligozoospermia. The depressed ATPase activity in the infertile men could be due to a reduction in intracellular adenosine triphosphate level and damage of spermal membranes caused by lipid peroxidation products. The most significant decrease in Ca 2 + , Mg 2+ -ATPase activity was observed in patients with leucocytospermia which could be explained by an excessive formation of the reactive oxygen species by the leucocytes. It is suggested that a decrease in the ion-exchanging ATPase activity may damage sperm functions and be one of possible causes of male infertility.