Ultrastructural observation of effect of moderate hypothermia on axonal damage in an animal model of diffuse axonal injury / 中华创伤杂志(英文版)
Chinese Journal of Traumatology
; (6): 355-360, 2002.
Article
in En
| WPRIM
| ID: wpr-332933
Responsible library:
WPRO
ABSTRACT
<p><b>OBJECTIVE</b>To investigate the effect of moderate hypothermia on responses of axonal cytoskeleton to axonal injury in the acute stage of injury.</p><p><b>METHODS</b>Of fifteen adult guinea pigs, twelve animals were subjected to stretch injury to the right optic nerves and divided into the normothermic group (n = 6) in which the animal's core temperature was maintained at 36.0-37.5 degrees C and the hypothermia group (n = 6) in which the core temperature was reduced to 32.0-32.5 degrees C after stretch injury. Remaining three animals sustained no injury to the right optic nerves and served as control group. Half of injured animals (n = 3) of either normothermic group or hypothermic group were killed at either 2 hours or 4 hours after injury. The ultrastructural changes of axonal cytoskeleton of the right optic nerve fibers from the animals were examined under a transmission electron microscope and analyzed by quantitative analysis with a computer image analysis system.</p><p><b>RESULTS</b>At 2 hours after stretch injury, there was a significant reduction in the mean number of microtubules (P < 0.001), and a significant increase in the mean intermicrotubule spacing (P < 0.05 or P < 0.01) in axons of all sizes in normothermic animals. The mean number of neurofilaments also decreased statistically (P < 0.01) in large and medium subgroups of axons in the same experimental group at 2 hours. By 4 hours, the large subgroup of axons in normothermic animals still demonstrated a significant decline in the mean number of microtubules (P < 0.01) and an increase in the mean intermicrotubule spacing (P < 0.05), while the medium and small subgroups of axons displayed a significant increase in the mean number of neurofilaments (P < 0.05) and reduction in the mean interneurofilament spacing (P < 0.05). On the contrary, either the mean number of microtubules and the mean intermicrotubule spacing, or the mean number of neurofilaments and interneurofilament spacing in axons of all sizes in hypothermic stretch-injured animals was not significant different from the mean values of sham-operated animals.</p><p><b>CONCLUSIONS</b>Posttraumatic moderate hypothermia induced immediately after axonal injury results in substantial protection of axonal cytoskeleton and ameliorates axonal damage.</p>
Full text:
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Index:
WPRIM
Main subject:
Optic Nerve
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Pathology
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Reference Values
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Axons
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Therapeutics
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Microscopy, Electron
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Random Allocation
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Probability
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Diffuse Axonal Injury
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Optic Nerve Injuries
Limits:
Animals
Language:
En
Journal:
Chinese Journal of Traumatology
Year:
2002
Type:
Article