[Pre- and postsynaptic effects of the calcium channel blocker verapamil in the nerve-muscle preparation]. / Pre- i postsinapticheskie éffekty blokatora kal'tsievykh kanalov verapamila v nervno-myshechnom soedinenii.

Verapamil did not change the amplitude of the miniature and multiquantal end-plate currents, synchronicity of the transmitter release and repetitive firing at the motor nerve endings. Verapamil shortened the decay of multiquantal currents, the effect being enhanced after acetylcholinesterase inhibition. In muscles with inhibited acetylcholinesterase, verapamil promoted the depression of successive end-late currents in rhythmic nerve stimulation. The data suggest that in skeletal muscles verapamil-sensitive calcium channels do not take part in physiological transmitter release or in chemical potentiation of the secretion after treatment with potassium channels blocking agents.