Neurofibril


Also found in: Dictionary, Medical, Wikipedia.
Related to Neurofibril: Neurofibril node

neurofibril

[¦nu̇r·ō′fī·brəl]
(neuroscience)
A fibril of a neuron, usually extending from the processes and traversing the cell body.

Neurofibril

 

a microscopic filament that is found upon treatment of nerve cells—neurons—and the longest outgrowths of the nerve cells—axons—with silver salts and other reagents.

In the late 19th and early 20th centuries, neurofibrils were ascribed the function of conducting nerve impulses. This view proved to be erroneous when it was found that nerve impulses are conducted by the external membrane of the neuron. Electron microscopy revealed two kinds of longitudinal neurofibrils in the outgrowths of neurons: neurotubules and neurofilaments. Neurotubules are from 20 to 25 nm in diameter and are formed from the protein tubulin; they are believed to transport substances along the axon. The threadlike neurofilaments are formed from a protein similar to the muscle protein actin. Neurofilaments are especially numerous in the movable terminal portions of growing axons.

References in periodicals archive ?
In the case of plaques, concentrating degenerative neurofibrils to the core substance were stained by such sliver stains.
These damaging plaques disrupt the neurofibrils in the brain by causing them to tangle up.
Also, insoluble aggregates of the amyloid beta-peptide (A[beta]) and neurofibrils composed of Tau protein are found in AD [30,31] and hyperphosphorylated Tau aggregation in demyelination areas in MS [32].