Figure 3. PIEZO2 is required for efficient micturition reflexes.
a, Example pressure traces from three female WT mice and b, three female HoxB8Cre;Piezo2f/f KO mice during continuous bladder filling. Scale in a also applies to b. c, Bladder contraction intervals (P<0.0001). d, bladder pressure five seconds before contraction peaks (P<0.0001). e, Heatmaps showing bladder contractions for six WT female mice and f, five HoxB8Cre;Piezo2f/f female KO mice. Color scale in e also applies to f. Each row represents bladder pressure during a single micturition event, with peaks aligned at 0. Arrows mark where data from one animal ends and another begins. g, Peak bladder pressures (P<0.0001) and h, area under the curve for bladder contractions (P<0.0001). i, Heatmap showing urethra activity, with each row from corresponding to bladder contraction events in e. j, Urethra activity from the HoxB8Cre;Piezo2f/f KO bladder contraction events shown in f. Scale in i also applies to j. k, Urethra activity during micturition (P<0.0001). l, Void volume measurements (P=0.03). P values from Student’s t-tests with Welch’s correction. N=6 WT and N=5 KO female mice for c through l. N=10–29 bladder contractions analyzed per mouse. m, Urination patterns of five WT mice and n, five HoxB8Cre;Piezo2f/f KO mice. o, Quantification of urine in the middle 50% of the cage (P=0.0001). N=11 female mice per group. p, Mice spend the same amount of time in cage center. q, H&E staining from WT and r, KO bladder sections, from littermates, 6–7 months, scale 100 μm. Muscle layer is marked by vertical lines. Scale for q and r is 200 μm. s, Bladder muscle wall thickness (N=5, P=0.016) and t, total bladder weights (N=9 and 8, P=0.0002). For o, s and t, Mann-Whitney test, all others are two-sided Student’s t-tests with Welch’s correction. Red lines indicate mean +/− standard deviation.