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Updated: Jun 19, 2026
08:25
Investigating Functional Regeneration in Organotypic Spinal Cord Co-cultures Grown on Multi-electrode Arrays
Published on: September 23, 2015
THE REGENERATIVE CYCLE OF MOTONEURONS, WITH SPECIAL REFERENCE TO PHOSPHATASE ACTIVITY.
1Poliomyelitis Research Center, Department of Epidemiology, Johns Hopkins University, Baltimore.
The Journal of Experimental Medicine
|October 30, 2009
Summary
Motoneuron regeneration involves shifts in nucleoprotein turnover and acid phosphatase activity. These changes support axon regrowth by supplying essential nucleotides for growth and organization during the regenerative cycle.
Area of Science:
- Neuroscience
- Cell Biology
- Biochemistry
Background:
- Motoneurons undergo a regenerative cycle after axon amputation.
- Nissl substance represents a steady state of cytoplasmic nucleoprotein.
- Chromatolysis involves a shift in nucleoprotein turnover towards degradation.
Purpose of the Study:
- To correlate morphological and chemical events in motoneuron cell bodies with the growth requirements of regenerating axons.
- To elucidate the role of Nissl substance and acid phosphatase in neuronal regeneration.
Main Methods:
- Observation of the regenerative cycle of motoneurons post-axon amputation.
- Analysis of morphological and chemical changes in cell bodies.
- Correlation of these changes with the growth requirements of regenerating axons.
Main Results:
- Early chromatolysis shows rapid Nissl substance depletion, linked to increased axon growth demands.
- Acid phosphatase activity increases during nucleoprotein degradation in chromatolysis.
- Recovery from chromatolysis coincides with axon lengthening, indicating restored nucleoprotein balance.
- Acid phosphatase activity peaks during Nissl substance transformation and declines as normal patterns restore.
Conclusions:
- Liberated nucleotides during chromatolysis may travel down the axon to support growth and organization.
- Nissl substance plays a continuous role in maintaining axon and myelin sheath integrity.
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