Figure 3.

Retrograde tracing analysis reveals that acute hypothermia resulted in greater sparing of brainstem axons projecting caudal to the injury site at 10 weeks post cervical spinal cord injury. (A) Retrograde labeling of neuronal somata with fast blue (FB), provided caudal to the lesion, shows that there was a greater sparing of brainstem projections (indicated by an increase in numbers of labeled neuronal perikarya) when acute hypothermia was applied. Investigation of specific brainstem neuronal populations revealed a significant increase in retrogradely labeled neurons in the reticular formation (B) but not the raphe (C) or vestibular nuclei (D) after hypothermia treatment. Recordings from uninjured controls are provided for comparison, and the data are expressed as the average ± standard error of the mean. *** p < 0.001 compared with normothermic controls. Reprinted with permission from [42], copyright Wiley-Liss, Inc., 2009.