Dixon plot analysis of the inhibitory activity of
compound 9B for NEP and APN. The experiments were performed
at 25°C in 50 mM Tris⋅HCl buffer (pH 7.4). (a)
The inhibitory potency of 9B for NEP was measured by using
DGNPA as substrate at the concentrations indicated (□,
5μm; ▴, 10 μM; ○, 25 μM; ■, 50
μM; ▵, 100 μM). (b) The inhibitory
potency of 9B for APN was measured by using Ala-PNA as
substrate at the concentrations indicated (□, 25 μM;
▴, 50 μM; ○, 100 μM; ■, 200 μM).
Each point of the Dixon plots represents the mean of triplicate
determinations. These experiments were repeated five times, leading to
a mean Ki value (± SEM) of 0.80 ±
0.05 nM for NEP and 2.5 ± 0.3 nM for APN.