Figure 2.

State-dependent stimulation restored both continence and efficient bladder emptying in male (n = 8) and female (n = 11) rats. (a) Cystometrograms from single experiments showing bladder pressure (black) and sphincter EMG (blue). Red lines indicate the duration of sensory pudendal stimulation (10 Hz, 1 T) to inhibit the bladder and promote storage. Brown lines above the traces indicate the duration of motor bursting stimulation (3 pulses at 40 Hz at the indicated burst repetition frequency) to activate the bladder and promote emptying. Average BC and VE for each type of trial for the example experiment are listed next to the traces. (b) BC for all experiments relative to controls. All relevant trials within an experiment were averaged resulting in a single data point for each experiment. Averages were 148% (males, P = 0.0008, n = 8) and 180% (females, P = 0.0002, n = 11). (c) VE for all stimulation conditions relative to controls. Continuous stimulation decreased VE relative to controls (males: 24%, P = 0.0006, n = 8; females: 12%, P < 0.0001, n = 11). State-dependent stimulation increased VE relative to continuous stimulation. In females motor-bursting stimulation increased VE beyond the stimulation during fill-only condition (2 Hz: P = 0.0049, n = 11; 5 Hz: P = 0.010, n = 10; 8 Hz: P = 0.0082, n = 7). In males, the largest increase in VE was the fill-only condition, increasing VE from 12 to 66% relative to control values (P = 0.011, n = 8). Box plots have a line at the median and the box extends from the estimated 25th to 75th percentiles. Lines beyond the box show the extent of data points that were not considered to be outliers (boxplot function, Matlab). Outliers are plotted as ‘+’ marks although all data were included for analysis. Paired t tests were used for BC comparisons. Mixed-effects analysis (i.e., an ANOVA like test) with two-stage linear step-up procedure of Benjamini, Krieger, and Yekutieli was used to determine the effect of condition on VE¹¹.