[TETRAMETHONIUM DERIVATIVES AS REVERSIBLE INHIBITORS OF DIFFERENT CHOLINESTERASES].

To study the influence of onium atom nature on anticholinesterase efficiency of elementorganic derivatives of tetramethylenbisonium compounds as reversible inhibitors of cholinesterase (ChE) - acetyl-ChE from human erythrocytes, butyryl-ChE from horse serum, ChE from the brain of frog Rana temporaria and ChEs from visual ganglia of Pacific squid Todarodes pacificus and individuals of Comman- der squid Berryteuthis magister from different habitats in the northwestern Pacific Ocean were investigated. Bisphosphonium inhibitors were significantly more potent effectors than bisammonium ones, but this may be associated with a significantly increased size and hydrophobicity of onium groups of the former. Bisammonium organosilicon compound and its monoammonium analogue were equally active reversible ChE inhibitors in mammals. First studied bis(phenyliodonium) derivative, which is characterized by a significant increase in the degree of hydrophobicity due to introduction of fluorine atoms in the interonium tetramethylene chain, also had marked anticholinesterase effects on mammalian ChE.