Figure 3
Time-lapse images following moderate midline fluid percussion or sham injury in Thy1-YFPH transgenic mice. hrGRIN lens assemblies were implanted just above the external capsule. Baseline images were acquired 1 week prior to induction of mFPI. Images of the same axons were acquired at 1 hr and at 3, 7, 14, and 30 days after mFPI. (a) Time-lapse images following sham injury. In sham animals, no apparent signs of damage were present in the series of images. The isolated swellings in the pre-injury images are normal and disappear over time (carets). These swellings are different from the multiple varicosities that appear on an injured axon after traumatic brain injury. (b) Moderately injured animals exhibited signs of axonal damage, including undulations (dashed arrows), disappearing axons (asterisk, 30 days), and axons with varicosities (solid arrows). Occasionally, undulated axons returned to baseline morphology and varicosities disappeared (arrowheads). Also, brighter fluorescent areas can occur where axons cross. Image z-stacks were examined to ensure that bright areas that look like varicosities were not axon crossings. Scale bars denote 10 µm for all images.
