Fig. 5
TrkA immunohistochemistry. (A) Density of crypt cells and comparison between controls and treatments. (B) Detail of control epithelium at high magnification; arrowheads: TrkA-positive crypt cells in the apical layer. Scale bar: 10 µm. (C) Representative micrograph of control tissue. (D1–3) Representative micrographs of lamellae exposed to 7 g L-1 of urea. (E1–3) Representative micrographs of lamellae exposed to 13.5 g L-1 of urea. (F1–3) Representative micrographs of lamellae exposed to 20 g L-1 of urea. Significant differences compared with controls are indicated by asterisks: *P < 0.05; **P < 0.01. Scale bar: 20 µm.