[Retraction of processes of remaining cells of the leech nervous system caused by neuron destruction].

Individual mechanosensory neurons in the leech segmental ganglia were eliminated in vivo by intracellular Pronase injection. 7-20 days later Lucifer Yellow was injected into mechanosensory neurons of the same modality in isolated ganglia. There was a clear evidence of retraction of neuronal processes. It is suggested that the leech nervous system structure is not necessarily fixed and can be changed after the death of individual neurons.