The involvement of ACh in the inhibitory effect of donepezil on macrophage MMP-9.

<p>(a) LPS treatment increased MMP-9 (LPS) in culture medium, which was inhibited by donepezil pretreatment (DPZ/LPS). However, ACh could not reproduce the inhibitory effect of donepezil (ACh/LPS). (b) Donepezil inhibited the LPS-induced MMP-9 even in the presence of a muscarinic ACh receptor blocker, atropine (Atr/DPZ/LPS), or a nicotinic ACh receptor blocker, mecamylamine (Mec/DPZ/LPS). Both blockers showed no effect on LPS-induced MMP-9 independently (Atr/LPS and Mec/LPS).