The effect of certain electrolytes on neuromuscular transmission disturbances evoked by direct action of phospholine...

In an isolated preparation of rat diaphragm stimulated indirectly (12 impulses per minute) after total inactivation of acetylcholinesterase phospholine reduced the amplitude of the response proportional to its concentration. The rise in the concentration of potassium, magnesium or calcium in the incubation fluid failed to alleviate the disturbances produced by phospholine. Phospholine increased significantly reduction of response amplitude caused by increased calcium and magnesium concentration and increased to a small extent response depression caused by raised potassium concentration. The obtained results, point out that phospholine exerts a direction on the neuromuscular junction which is connected with the postsynaptic action of this agent.