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Proceedings of the National Academy of Sciences of the United States of America logoLink to Proceedings of the National Academy of Sciences of the United States of America
. 1980 Feb;77(2):1209–1213. doi: 10.1073/pnas.77.2.1209

Large and persistent electrical currents enter the transected lamprey spinal cord.

R B Borgens, L F Jaffe, M J Cohen
PMCID: PMC348455  PMID: 6928670

Abstract

The electrical currents at the surface of the proximal portion of an isolated and transected lamprey spinal cord were measured with an extracellular vibrating probe. Soon after transection, currents of about 0.5 mA/cm2 enter the cut surface of the spinal cord. These currents fall to about a quarter of their initial value within an hour; within the next 2 days they gradually decline from about 100 microA/cm2 to about 4 microA/cm2; they then remain constant up to 6 days posttransection, when the measurements were ended. The pattern of current entry included substantial peaks opposite (and presumably into) the cut ends of giant axons. Response to changes in the ionic composition of the medium indicates that about half of the injury current consists of Na+, and that much of the rest may consist of Ca2+. The measured influx of ions, which adds up to several coulombs per cm2 in a few days, should radically alter the ionic composition of the terminal few millimeters of neural tissue. Thus it may be important in the degenerative and regenerative responses of neurons to axotomy.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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