RESUMO
<p><b>OBJECTIVE</b>To investigate the effects of interferon-gamma (IFN-gamma) and tumor necrosis factor alpha (TNF-gamma) on the sperm acrosin activity and the rate of acrosome reaction and to probe into their mechanisms.</p><p><b>METHODS</b>Thirty-six nearly normal semen samples were treated with IFN-gamma and/or TNF-alpha after isolated by 75% Percoll. The sperm acrosin activity was tested by the method of BAEE/ADH Unity, the rate of acrosome reaction observed by Triple-stain technique, the NO concentration measured by HPLC and the activities of Na+ -K+ -ATPase, Ca2+ -ATPase and SOD assayed by kit method.</p><p><b>RESULTS</b>Both IFN-gamma and TNF-gamma could decrease sperm acrosin activity and acrosome reaction (P < 0.05 or P < 0.01). TNF-alpha showed stronger inhibiting effect, IFN-gamma markedly reduced the activities of Na+ -K+ -ATPase, Ca2+ -ATPase and SOD in sperm (P < 0.01), and their synergistic action was weaker. However TNF-alpha produced hardly any effect on Na+ -K+ -ATPase and Ca2+ -ATPase. The NO concentration in sperm was significantly increased by IFN-gamma and/or TNF-alpha (P < 0.01).</p><p><b>CONCLUSION</b>IFN-gamma and TNF-alpha have some inhibiting effect on sperm acrosin activity and the rate of acrosome reaction, which could be attributed to their influence on the activities of Na+ -K+ -ATPase, Ca2+ -ATPase and SOD, the NO concentration and so on.</p>