Figure 3

FDPS immunoreactivity (green) in the circumvallate papillae (CV) and the fungiform papillae (FP) of mice following the administration of risedronate (15 mg/kg body weight) for 28 days. (A) Many FDPS-positive cells were also carbonic anhydrase-4 (CA4)-positive (magenta). Arrowheads denote FDPS + CA4 double-positive cells. (B,C) A few FDPS-positive cells expressed taste receptor type 1 member 3 (T1R3, red) or gustducin (cyan). Dotted lines outline individual taste buds. Scale bars: 25 μm. (D) The number of taste buds after the administration of vehicle or risedronate for 28 days in the CV. The vehicle-treated group (Ctrl, white bar) and risedronate-treated group (Rise, blue bar) exhibited no significant differences in the number of taste buds. Data are presented as the mean ± SEM (n = 10 section slices from the middle part of 5 circumvallate papillae). P > 0.05 (Student's t-test; see Table 3). (E,F) The number of cells per taste bud after the administration of vehicle or risedronate for 28 days in the CV (E) and FP (F). The vehicle-treated group (Ctrl, white bars) and risedronate-treated group (Rise, blue bars) exhibited no significant differences in the number of taste bud cells in the CV, cells expressing FDPS, CA4 or both FDPS and CA4 (Merge). Data are presented as the mean ± SEM (n = 213–245 CV taste buds, n = 100–102 FP taste buds). P > 0.05 (Student's t-test; see Table 3).