Contribution of de novo synthesis of acetylcholinesterase to spontaneous recovery of neuromuscular transmission following soman intoxication.

The role of the de novo synthesis of acetylcholinesterase in the spontaneous recovery of neuromuscular transmission was studied in diaphragms isolated from soman-intoxicated rats. Ten minutes after soman (3 X LD50 i.v.), the acetylcholinesterase activity and the neuromuscular transmission appeared to be completely blocked. Acetylcholinesterase activity in endplate and endplate-free regions recovered linearly during a 3 h experiment (1.5 and 2.9%h, respectively); and neuromuscular transmission was also improved. Since both inhibition of the de novo synthesis of acetylcholinesterase by cycloheximide and the re-inhibition of acetylcholinesterase in vitro by soman did not affect the improvement of neuromuscular transmission, it was concluded that this recovery of neuromuscular transmission can not be attributed to synthesis of new acetylcholinesterase.