β-catenin immunolocalization in experimental obstructive nephropathy. We labeled kidneys of sham-operated mice and of mice which had been challenged with UUO with antibodies specific to (A) total β-catenin or with antibodies specific for (B) non-phosphorylated β-catenin (indicative of active canonical signaling). The pictures display representative photomicrographs of each groups, positive immunostaining is indicated by brown precipitate. The arrows highlight robust expression of β-catenin in dilated tubules. Scale bars: 100 μm. UUO, unilateral ureteral obstruction.