[Inhibitory effect of verapamil on the acetylcholinesterase activity of skeletal muscle sarcolemma].
It has been found that verapamil reversibly inhibits "in vitro" the activity of membrane--bound and solubilized sarcolemmal acetylcholinesterase. The kinetic analysis has demonstrated a competitive type of inhibition at verapamil concentrations less than 100 mkM and a mixed one at higher verapamil concentrations. The apparent Ki values are similar to or approximately 5,0.10(-5) M and similar to or approximately 3,0.10(-4) M for both types of inhibition, respectively. The effect of vereapamil and Ca2+ on acetylcholinesterase is independent and non-competitive. An increase in the ionic strength leads to a decrease of the verapamil-induced inhibition of acetylcholinesterase. It is suggested that verapamil interacts with the anionic groups of both free and acylated enzyme.
D000818:Animals; D001667:Binding, Competitive; D002118:Calcium / Q000494:pharmacology; D002800:Cholinesterase Inhibitors; D007700:Kinetics; D009132:Muscles / Q000201:enzymology*; D009994:Osmolar Concentration; D011485:Protein Binding; D011817:Rabbits; D012508:Sarcolemma / Q000201:enzymology*; D014700:Verapamil / Q000494:pharmacology*
D002800:Cholinesterase Inhibitors; D014700:Verapamil; D002118:Calcium
Izuchenie ingibiruiushchego deĭstviia verapamila na atsetilkholinesteraznuiu aktivnost' sarkolemmy skeletnykh myshts.