Summary
Traumatic head injury has long been associated with the genesis of reactive axonal change, which many believe to be a major factor in influencing neurological outcome. Although much significance has been attached to such a traumatically induced axonal change, little information exists as to whether such a reactive change occurs as an isolated event or rather as an event associated with concomitant focal tissue damage, possibly involving related neuronal somal and dendritic elements. This issue was critically assessed in mechanically brain-injured cats in which the anterograde axonal transport of horseradish peroxidase was employed to detect reactive axonal change. Following such traumatically induced reactive axonal change over a 21-day post-traumatic period, altered axons were consistently observed within the red, vestibular and reticular nuclei and any evidence for concomitant change within the related neuronal somal and dendritic elements was assessed using light and electron microscopy. Typically, such axonal change occurred without any evidence of focally related somatic or dendritic alteration. Isolated examples of reactive axons approximating neurons undergoing chromatolysis were observed. However, such neuronal chromatolytic change appeared not to be a primary response to trauma, but rather a response secondary to severence of these neurons' axonal projections. The results of this study demonstrate that, in mild to moderate head injury, reactive axonal change does occur in isolation from other forms of focal parenchymal abnormality. This finding, therefore, emphasizes the concept that the number of axons damaged is most likely related to the magnitude of any ensuing neurological abnormality.
Similar content being viewed by others
References
Adams JH, Mitchell DE, Graham DI, Doyle D (1977) Diffuse brain damage of immediate impact type: its relationship to primary brain-stem damage in head injury. Brain 100:489–502
Adams JH, Graham DI, Murray LS, Scott G (1982) Diffuse axonal injury due to nonmissile head injury in humans. Ann Neurol 12:557–563
Barron KD (1982) Axon reaction and its relevance to CNS trauma. In: Grossman RG, Gildenberg PL (eds) Head injuries: basic and clinical aspects. Raven Press, New York, pp 15–21
Barron KD, Dentinger MP, Nelson LR, Miney J (1975) Ultrastructure of axonal reaction in red nucleus of cat. J Neuropathol Exp Neurol 34:222–248
Chen DH, Chamber WW, Liu CN (1977) Synaptic displacement in intracentral neurons of Clarke's nucleus following axotomy in cat. Exp Neurol 57:1026–1044
Friede RL (1960) Specific cord damage at the atlas level as a pathogenic mechanism in cerebral concussion. J Neuropathol Exp Neurol 19:266–279
Friede RL (1961) Experimental concussion acceleration. Arch Neurol 4: 109–122
Gennarelli TA, Thibault LE, Adams JH, Graham DI, Thompson CJ, Marcincin RP (1982) Diffuse axonal injury and traumatic coma in primate. Ann Neurol 12:564–575
Hayes RL, Pechura CM, Katayama Y, Povlishock JT, Giebel ML, Becker DP (1984) Activation of pontine cholinergic sites implicated in unconsciousness following cerebral concussion in cat. Science 223:301–303
Peerless SJ, Rewcastle NB (1967) Shear injuries of the brain. Can Med Assoc J 96:577–582
Povlishock JT, Becker DP (1985) Fate of reactive axonal swellings induced by head injury. Lab Invest 52:540–552
Povlishock JT, Becker DP, Miller JD, Jenkins LW, Dietrich WD (1979) The morphopathologic substrates of concussion? Acta Neuropathol (Berl) 47:1–11
Povlishock JT, Becker DP, Cheng CLY, Vaughan GW (1983) Axonal change in minor head injury. J Neuropathol Exp Neurol 42:225–242
Strich SJ (1961) Shearing of nerve fibers as a cause of brain damage due to head injury Lancet II:443–448
Torvik A, Soreide AJ (1975) The perineuronal glial reaction after axotomy. Brain Res 95:519–529
Windle WF, Groat RA, Fox CA (1944) Experimental structural alterations in the brain during and after concussion. Surg Gynecol Obstet 79:561–592
Author information
Authors and Affiliations
Additional information
Supported by NIH grants NS 12587 and NS 20193 designated as a Javits Neuroscience Investigator Award
Rights and permissions
About this article
Cite this article
Povlishock, J.T. Traumatically induced axonal damage without concomitant change in focally related neuronal somata and dendrites. Acta Neuropathol 70, 53–59 (1986). https://doi.org/10.1007/BF00689514
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00689514