A, Pleiotrophin expression upregulated in the cerebral cortex by the cuprizone-induced demyelination. Anti-PTN staining of wild-type (+/+) and Ptprz-deficient (−/−) mouse brains. Scale bars, 25 μm. B, Scatterplot showing the percentage of anti-PTN positive neuron in the cortex. Open circles, Wild-type mouse; closed circles, Ptprz-deficient mouse. n = 10 for each group. No genotypic differences were detected by a two-way ANOVA.