Compression of a nerve causes loss of afferent and efferent information in it. What is the physiological basis of this?
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Seems like it results from a loss of blood flow as the Vasa Nervorum is compressed. Vessels, like arteries or tubules within the kidney, are compressible since they have a vacuous lumen, while an axon is cellular and resists compression. I was thrown off a bit by an answer by a Bryan Krause to this question here, Neurons during Numb feeling, "the feeling of paresthesia is not from loss of blood flow", but, seems like that person was wrong.
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$\begingroup$ Another commenter noted my comment was mentioned here; it was made in haste and probably misleading, probably I should have added a word and said "complete loss of blood flow". I was referring to the article linked in the question there that implied that blood flow to entire limbs is cut off; if this would happen there would certainly be tissue damage in short order. The distinction I meant to make was between compressing major blood vessels versus compressing nerves themselves. $\endgroup$– Bryan Krause ♦May 26, 2020 at 20:59
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$\begingroup$ It can likely happen if vessels proximal to vasa nervorum are compressed too. Loss of blood flow to vasa nervorum does cause tissue damage, but increases in severity with time. And for the axon conductance to shut down (however it is axons actually do conduct signals), likely very deplete of oxygen, glucose, or whatever it is lacking that makes it not signal anymore. $\endgroup$ May 27, 2020 at 10:05
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$\begingroup$ @BryanKrause if its caused by oxygen/glucose deprivation, that proves the saltatory conduction theory that the action potential has to "boost" itself at the nodes of Ranvier. do you happen to know if electrolyte exchange is in any way stifled in the peripheral nervous system where the nodes of ranvier are a bit "covered" with projections from the myelin cell? $\endgroup$ May 27, 2020 at 14:31