Regeneration of nerves / by F.W. Mott, W.D. Halliburton and Arthur Edmonds.

  • Mott, F. W. (Frederick Walker), 1853-1926
Date:
[1906]
Catalogue details

Licence: In copyright

Credit: Regeneration of nerves / by F.W. Mott, W.D. Halliburton and Arthur Edmonds. Source: Wellcome Collection.

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    are growths from the central ends of divided nerve trunks. The experimental facts recorded by those who, like Bethe and Kennedy, hold the opposite view are susceptible of easy explanation, mainly on the lines emphasised by Langley and Anderson of accidental and unnoticed connection of the peripheral segments with the central nervous system by means of other nerves cut through in the operation. If such connection is effectually prevented, real regeneration of structure and restoration of function never occurs. Moreover, the regenerated fibres always degenerate in a peripheral direction, and in a peripheral direction only, when the link that binds them to the central nervous system is again severed. Perhaps the most striking of the facts brought out in our own work is in reference to the development of the medullary sheath ; this appendage of the axis cylinder appears earliest at situations near the point where the ends of a nerve have been joined together, and reaches the distal portions later. What takes place in the peripheral segment of a divided nerve is a mul- tiplication, elongation and union into long chains of the neurilemmal cells. The same change is even more vigorous at the central termination of the cut nerve; and the view of the phagocytic and nutritive function which we attribute to this sheath has been supported independently by some striking observations of Graham Kerr which we have fully referred to. At the central end this nutritive function is effective and provides lor the nourish- ment of the actively lengthening axis cylinders. At the peripheral end, unless the axons reach it, it is ineffective in so far as any real new formation of nerve-fibres is concerned. Tf, however, the axons reach the peripheral segment, the work of the neurilemmal cells has not been useless, for they provide the supporting and nutritive elements necessary for its continued and successful growth. The neurilemmal activity appears to be essential, foi without it, as in the central nervous system, regeneration does not take place. According to Graham Kerr the formation of neuro-fibrilke may possibly take place in the protoplasmic residue of the degenerated axis cylinder, according to Marinesco this property is assigned to the neurilemmal elements themselves, a proposition we regard as extremely improbable, seeing that these elements are mesoblastic.- In either case these two observers considei that the neuro-fibrillse, however formed, are ineffective until they are activated by union with those of the central axons. Our own observations do not entirely exclude this view, but on the other hand (as we have never seen these fibrillae in the peripheral segment unless union with the central end has occurred) they lend it no support. All our facts are readily explic- able, however, on the theory that the nerve-fibres are growths from the central ends of divided nerves.