[The effect of acetylcholine on neuromuscular transmission in the fatigued rat diaphragm with blocked acetylcholinesterase].

The rat phrenic-diaphragm preparations with amine-inhibited acetylcholinesterase were fatigued by rhythmical nerve stimulation. Tetanization of the nerve by bursts of stimuli 20/sec led to a long-term recovery of muscle contractions of the fatigued muscles. The recovery was completely abolished by tubocurarine and partially--by atropine. Acetylcholine bathing simulated the effect of tetanization. Probable mechanisms of this phenomenon are discussed.