[Nandeshi: a powerful inhibitor of human acrosin activity].

Objective: To evaluate the inhibitory effect of Nandeshi, an acrosin inhibitor, on human acrosin activity.

Methods: We collected sperm samples from 10 healthy fertile men and cultured them with Nandeshi at 30 degrees C for 5 minutes at the concentrations of 0. 100, 0.120, 0.144, 0.173, 0.207, 0.249, 0.299, 0.358 and 0.430 mmol/L, with the controls treated with a well-known acrosin inhibitor N-alpha-p-tosyl-L-lysine chloromethylketone (TLCK) at 150.0, 189.8, 213.6, 240.3, 270.3, 304.1 and 342.1 mmol/L. Then we determined the residual activity of human acrosin by improved Kennedy assay.

Results: The residual activity of acrosin was negatively correlated with the Nandeshi concentration, and Nandeshi exhibited an inhibition rate about 800 times that of TLCK.

Conclusion: Nandeshi has a powerful inhibitory effect on human acrosin, and improved Kennedy assay is a simple, practical and highly sensitive technique for the detection of human acrosin activity.