Table 1.

EMG and urodynamic properties recorded during voiding in chronically implanted rats

Property	Daily	Dark	Light	P Value, Dark vs. Lighta
Number of voidsb	22.4 ± 1.4	15.0 ± 1.0	7.3 ± 0.5	0.0001
Intervoid interval, s	75.5 ± 4.1	56.2 ± 3.4	99.9 ± 5.6	0.0001
Daily urine output, g/200 g body wtc	9.8 ± 0.6	5.5 ± 0.4	4.2 ± 0.3	0.0001
Urine output/void, g/200 g body wt	0.49 ± 0.03	0.40 ± 0.03	0.60 ± 0.03	0.0001
Void duration, s	2.2 ± 0.1	2.0 ± 0.1	2.5 ± 0.1	0.0001
EMG amplitude, μV	28.6 ± 2.7	29.9 ± 2.8	28.5 ± 2.7	0.002
Bursting powerd, % of total	14.8 ± 1.4	14.3 ± 1.3	15.9 ± 1.6	0.005
Bursting timee, s	0.93 ± 0.14	0.82 ± 0.14	1.16 ± 0.17	0.001
Dominant frequencyf, Hz	6.7 ± 0.1	7.1 ± 0.1	6.7 ± 0.1	0.006

Values are means ± SE.

EMG, electromyography.

^aAnalysis by paired t-test within each animal for light vs. dark conditions.

^bNumber of voids per 24 h (daily) and per 12 h (dark, light).

^cCumulative urine weight per 24 h (daily) and per 12 h (dark, light).

^dAverage power in the bursting frequency range expressed as percent of average total power for all voiding events.

^eCumulative time during the void in which the bursting power exceeds the power in the same range, expressed as percentage of total power of amplitude-matched non-voiding epochs, by ±2 SD.

^fAverage frequency with highest power in bursting frequency range from all spectra calculated during the void.