Figure 6.

Memantine promotes contralesional corticorubral plasticity. (a) Midline-crossing fibers originating from the contralesional motor cortex in direction to the ipsilesional parvocellular red nucleus were evaluated by injection of the anterograde tract tracer BDA into the contralesional motor cortex at 42 dpt. (b) Percentage of BDA-labeled midline-crossing fibers after subcutaneous delivery of vehicle or memantine (4 or 20 mg/kg/d). Note the significant increase of midline-crossing fibers in response to 20 mg/kg/d, but not 4 mg/kg/d memantine (representative microphotographs with magnified inlets are shown in (c)). (d) Total area of the contralesional pyramidal tract at the level of the red nucleus, which does not change in response to memantine, indicating the absence of contralesional corticospinal tract degeneration. Results are medians (lines inside boxes)/means (crosses inside boxes) ± IQR (boxes) and minimum/maximum data (elongation lines) (n = 18 animals/group). Data were analyzed by one-way ANOVA followed by LSD tests. *p < 0.05 compared with ischemic vehicle. Bar, 100 µm (B).