Table 1.

the effect of protease inhibitors on the activity of NK-Bs

inhibitor	residual activity (%)
	1 mM	2 mM
β-mercaptoethanol	97.48 ± 3.72	92.90 ± 3.51
EDTA	109.46 ± 2.06	105.11 ± 4.50
PMSF	40.17 ± 1.84	3.02 ± 0.36
control	100.00 ± 1.62	100.00 ± 1.27