ABSTRACT
Here we present novel information on non-classical functions of cholinesterases and on a cross-talk linking the two enzymes AChE and BChE. The first part of the article is focussed on the regulation of ChEs and the effects acquired when one of the proteins is knocked down (siRNA for BChE, AChE knock-out mouse). In the second part evidence is presented showing that AChE may exert adhesive properties through its binding to laminin, thus being involved in cell-matrix or cell-cell communication.
Subject(s)
Acetylcholinesterase/metabolism , Butyrylcholinesterase/metabolism , Acetylcholinesterase/genetics , Amidohydrolases/metabolism , Animals , Butyrylcholinesterase/genetics , Cell Adhesion , Gene Expression Regulation, Developmental , Gene Expression Regulation, Enzymologic , Laminin/metabolism , Mice , Protein Binding , RatsABSTRACT
Benactyzine and drofenine are widely used anticholinergic drugs. Benactyzine is used to treat organophosphate poisoning and drofenine acts on smooth muscle to stop muscle spasms. Both of these drugs are esters. After they enter the bloodstream, they will interact with butyrylcholinesterase (BChE; acylcholine acyl hydrolase: EC 3.1.1.8), which has an ability to hydrolyze a wide variety of esters. Therefore, the kinetic analysis of their inhibitory effects on human serum BChE was examined using butyrylthiocholine as substrate. Both drugs were competitive inhibitors of BChE and the Ki values of benactyzine and drofenine were calculated to be 0.010 +/- 0.001 and 0.003 +/- 0.000 mM, respectively, using the Systat (version 5.03, 1991) nonlinear regression analysis software package. According to these parameters, drofenine is a more potent competitive inhibitor of BChE than benactyzine.