Recovery of acetylcholinesterase (AChE) activity after nerve crush was observed at second week in soleus (slow-extensor) and plantaris (fast-extensor) muscles whereas the same was observed in extensor digitorum longus (fast-flexor) only after third week. In contrast to earlier observations the AChE was found to exhibit specific transient elevations with intermittent reversal to control values in different type of skeletal muscles during later periods of reinnervation.