Fig. 3. Videocystometry reveals the acute effect of TRPV1 activation of E_voiding.

(A and B) Pressure and volume traces comparing the effects of intravesical administration of vehicle (A) or the TRPV1 agonist capsaicin (100 μM; B). After a baseline period of 30 min, the intravesical perfusion solution was switched to a solution containing either vehicle or capsaicin. During the switch, recording was stopped during the indicated times. The solid blue line connects the E_voiding for individual voids. Dotted lines indicate the lowest and highest E_voiding during the baseline period. (C) Comparison of videocystometry parameters before and after the switch to either vehicle or capsaicin. Bar charts indicate means ± SD, with data points from individual animals shown along. RV_min and E_voiding,max represent the single lowest residual volume (RV) and single largest E_voiding, respectively, recorded before and after the switch. Statistical comparison of the relative change of the indicated parameters (after/before) between capsaicin-treated (n = 5) and vehicle-treated (n = 6) animals was performed using a two-tailed, unpaired t test. Values for the relative changes (after/before × 100%; vehicle versus capsaicin) were as follows: P_max, 89.1 ± 8.3 versus 86.6 ± 8.4%; RV_min, 97.0 ± 6.5 versus 57.4 ± 6.8%; E_voiding,max, 99.7 ± 0.3 versus 115.7 ± 7.2%; UFR, 107.6 ± 5.4 versus 109.0 ± 6.4%.