[Effect of the cholinesterase inhibitor armin on meuromuscular synapse function of the frog sartorius muscle].

The organophosphurus inhibitor of cholinesterases armin(2-10-9--2-10-4 M) prolonged postjunction potentials and in concentration 2-10-9--2-10-7 M increased the amplitude of miniature end-plate potentials (m. e. p. p. s and quantum content of e.p.p.s. These parameters were increased again after washing. Thus, armin (2-10-9--2-10-7 M) exerts anticholinesterase effect only. In concentrations 2-10-6--2-10-4M, in addition to the anticholinesterase effect, it affects presynaptic membrane and inhibits postsynaptic membrane cholinoreceptors.