Figure S3.

Water deprivation test and bumetanide-induced diuresis and natriuresis. β3-AR-null mice (β3-AR-/-) and their age-matched controls (β3-AR+/+) (N = 8 for each group), were individually housed in metabolic cages for 24 hours, then 4 animals per group were subjected to water deprivation for 24 hours, while 4 animals had free access to water (basal). The 24-hour urine output (A) and urine osmolality (B) of control animals were set as 100%. Urine output of water-deprived animals was reduced of 32% in β3-AR+/+ mice and of 40% in β3-AR-/- mice. Urine osmolality of water-deprived animals was increased of 27% in β3-AR+/+ mice and of 28% in β3-AR-/- mice. Data are provided as mean ± SEM. Significant differences between means were tested by one-way analysis of variance ANOVA with Newman-Keuls’s post-test. **P < 0.001, *P <0.05 No significant interstrain differences were observed. Urine output (C) and natriuresis (D) after the i.p. injection of vehicle or 40 mg/kg bumetanide for 4 hours in β3-AR+/+ and β3-AR-/- mice. The 4-hour urine output and urine Na+ excretion of control animals was set as 100% (n = 5). Data are provided as mean ± SEM. Significant differences between means were tested by one-way analysis of variance ANOVA with Newman-Keuls’s post-test. ***P < 0.0001 for intrastrain differences between vehicle and bumetanide treatments; §P < 0.01 for interstrain differences in the effects of bumetanide. The bumetanide-induced natriuresis was significantly attenuated in β3-AR-/- mice compared with β3-AR+/+.