Stable in vivo imaging of densely populated glia, axons and blood vessels in the mouse spinal cord using two-photon microscopy.

In vivo imaging has revolutionized our understanding of biological processes in brain physiology and pathology. However, breathing-induced movement artifacts have impeded the application of this powerful tool in studies of the living spinal cord. Here we describe in detail a method to image stably and repetitively, using two-photon microscopy, the living spinal tissue in mice with dense fluorescent cells or axons, without the need for animal intubation or image post-processing. This simplified technique can greatly expand the application of in vivo imaging to study spinal cord injury, regeneration, physiology and disease.