Figure 6.
Enzyme inhibition kinetic analysis of duloxetine against human butyrylcholinesterase. (A) Duloxetine is most potent at low substrate concentrations (up to 0.5 mM) with a Ki of 0.21 μM compared to a high substrate concentration of up to 5 mM (see Figure 5A). This is most likely due to duloxetine being a competitive BChE inhibitor. (B) Similar analyses at low substrate concentrations indicate that the ethopropazine affinity is not affected (see Figure 5C). This is because it acts as a mixed-competitive inhibitor. Nonlinear regression analyses were done with GraphPad Prism 9. Data are given as mean ± SD.