Figure 4.

DCS exerted polarity-specific effects on fiber volume, density, and outgrowth direction. A, Anodal DCS significantly enhanced the TH-ir fiber volume surrounding the graft. B, Representative 3D reconstruction of TH-fiber volume in the three groups. Properties of binarized images stacks of individual fiber volumes were adapted to the original slice thickness (40 µm) and spacing between consecutive slices (120 µm). ImageJ plugin 3D viewer was used to render a 3D model of the stack. Stacks are rotated around the y-axis at an angle of 30°, i.e., volumes are shown from a diagonal perspective. Distance between axes tick marks is set to 1000 µm. Note that the fiber volume is largest in the anodal DCS condition. C, Integrated fiber density, the relative OD of TH-ir fibers multiplied by the reinnervated area, was significantly higher in the anodal DCS group compared to sham DCS. D, Both active stimulation paradigms resulted in a larger amount of TH-ir fiber outgrowth directed toward the cranial electrode (dorsal), with only anodal DCS reaching the level of significance. Mean ± SEM; two-tailed Student’s t test each active stimulation versus sham; *p < 0.05.