The localization of acetylcholinesterase in the optic lobe in the developing chick embryo

The localization of acetylcholinesterase (AChE) in the optic lobe in the developing chick embryo was studied histochemically and biochemically. The histochemical reaction of AChE increased remarkably between stage 42 and 44 especially in the neuropile. The increase of the biochemical activity of the AChE in the synaptic membrane fraction occurred at a later stage than that in the microsomal fraction. These findings can be interpreted as the result of axonal transport of the enzyme from the synthetic to the synaptic site.