SEVERE injury to the axon produces detectable histological changes in the cell body as well as proximal and distal parts of the injured fiber. This retrograde reaction in the perikaryon is commonly known as chromatolysis or chromolysis because of the apparent decrease in basophilic material in the cytoplasm. In crush injury of the axon with preservation of the sheath (termed axonotmesis by Seddon1) regeneration of the neuron may occur in a shorter time, than after complete section of the nerve.
There have been many studies of motoneurons during degeneration and regeneration,2-8 but histochemical studies of the enzymes in these neurons are few. Different authors have investigated alkaline and acid phosphatases, thiamine pyrophosphatase (TPPase), succinic dehydrogenase, and cytochrome oxidase in chromatolytic neurons9-12 but metabolic significance of these changes is not known.
In the present study we have investigated a number of oxidative and hydrolytic enzymes by histochemical