The Effect of Ligation Combined with Section on Anterograde Axonal Transport in Rabbit Hypoglossal Nerve

The axonal transport of radiolabeled slow phase proteins and fast phase glycoproteins was studied in rabbit hypoglossal nerve one week after axotomy. The nerves were ligated and cut to prevent axonal regeneration into the distal stump. In this situation of obstructed axonal outgrowth, the axonal transport of these components into the proximal part of the nerve was increased. This increase, however, was significantly less pronounced compared with the increase previously found after nerve crush, when the axons were free to regenerate. The results suggest that the axonal transport response concerning structural axonal proteins after nerve lesions depends on the type of trauma, and that the neuronal export of these components during regeneration is modified if axonal outgrowth is impaired. The results are discussed in the light of the present understanding of the role of axonal transport in nerve regeneration.