On the Studies of Detrusor-Sphincter Synergia of Wistar Rats via Karhunen-Loève Expansion
In normal Wistar rats, we have found that the voiding of the bladder has a synergic cooperation between the detrusor and the sphincter. On the contrary, the suprasacral spinal cord injured (SCI) rats usually exhibit dyssynergic contractions of the bladder and the external urethral sphincter (EUS). In this study, the cystometrograms (CMG) of the detrusor and the electromyograms (EMG) of the EUS of intact and SCI female Wistar rats are used to investigate the eigenmodes of synergic cooperation during micturition via Karhunen-Loève expansion (KLE). Here we show that the three different phases of urination of intact rats: initial, bursting and relaxation phase, have different number of eigenmodes. The SCI rats are also investigated with the KLE method. Results have indicated that our understanding of micturition mechanism of Wistar rats can be mightily improved.