[Effect of berberine, glaucine, stephaglabrine and sanguiritrine on neuromuscular transmission].

Natural alkaloid drugs, glaucine, stephaglabrine and sanguiritrine, are shown to affect the synaptic transmission in a fairly complicated manner and seem to involve several different mechanisms of action. These substances as well as berberine reduce amplitude of the spontaneous miniature end plate potentials in a frog neuromuscular junction. At low concentrations all the mentioned alkaloids diminish frequency of miniature potentials, but increase it when their concentration exceeds a certain value.