TY - JOUR
T1 - A Surviving Intact Branch Stabilizes Remaining Axon Architecture after Injury as Revealed by InVivo Imaging in the Mouse Spinal Cord
AU - Lorenzana, Ariana O.
AU - Lee, Jae K.
AU - Mui, Matthew
AU - Chang, Amy
AU - Zheng, Binhai
N1 - Funding Information:
Supported by grants from the Dana Foundation, NIH/NINDS (R01NS054734, R21NS088536) and the Roman Reed Fund to B.Z.; NRSA predoctoral fellowship F31NS074867 to A.O.L.; NRSA postdoctoral fellowship F32NS056697 to J.K.L. In vivo imaging was conducted at the UCSD Neuroscience Microscopy Imaging Core managed by Jennifer Santini (P30NS047101). We thank Dimitrios Davalos for demoing laser ablation techniques; Jeffrey Kwan, Andrea Chan, Benjamin Gallarda, Omeed Ghassemi, and Pearl Shih for technical assistance; Mark Lawson for advice on statistical analyses; Cédric Geoffroy for helpful discussions; and Le Ma, Meifan Chen, and Jessica Meves for helpful comments on the manuscript.
PY - 2015/5/20
Y1 - 2015/5/20
N2 - The complex morphology of axons presents a challenge in understanding axonal responses to injury and disease. By invivo two-photon imaging of spinal dorsal column sensory axons, we systematically examined the effect of injury location relative to the main bifurcation point on axon degeneration and regeneration following highly localized laser injuries. Retrograde but not anterograde degeneration was strongly blocked at the bifurcation point at both the acute and subacute phases. Eliminating either the ascending or descending branch led to a poor regenerative response, while eliminating both led to a strong regenerative response. Thus, a surviving intact branch suppresses both retrograde degeneration and regeneration of the injured branch, thereby preserving the remaining axon architecture. Regenerating axons exhibited a dynamic pattern with alternating phases of regeneration and pruning over a chronic period. Invivo imaging continues to reveal new insights on axonal responses to injury in the mammalian spinal cord.
AB - The complex morphology of axons presents a challenge in understanding axonal responses to injury and disease. By invivo two-photon imaging of spinal dorsal column sensory axons, we systematically examined the effect of injury location relative to the main bifurcation point on axon degeneration and regeneration following highly localized laser injuries. Retrograde but not anterograde degeneration was strongly blocked at the bifurcation point at both the acute and subacute phases. Eliminating either the ascending or descending branch led to a poor regenerative response, while eliminating both led to a strong regenerative response. Thus, a surviving intact branch suppresses both retrograde degeneration and regeneration of the injured branch, thereby preserving the remaining axon architecture. Regenerating axons exhibited a dynamic pattern with alternating phases of regeneration and pruning over a chronic period. Invivo imaging continues to reveal new insights on axonal responses to injury in the mammalian spinal cord.
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U2 - 10.1016/j.neuron.2015.03.061
DO - 10.1016/j.neuron.2015.03.061
M3 - Article
C2 - 25937174
AN - SCOPUS:84930273114
VL - 86
SP - 947
EP - 954
JO - Neuron
JF - Neuron
SN - 0896-6273
IS - 4
ER -