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Aims: The aim of this study was to determine if the duration of the micturition reflex modulation could be prolonged by repeated periods of afferent stimulation in the decorticated rat., Methods: Eighteen female Sprague-Dawley rats were used for the study, 10 for intravesical electrical stimulation (IVES), and 8 for Ano-genital pudendal afferents stimulation. Repeated constant flow cystometries were performed with body-warm saline (0.06-0.1 mL/min) at about 10 min interval. The selected afferents were stimulated continuously for 5 min at maximal intensity. The same stimulation was repeated six times with a pause of 5 min between the stimulations. The mean threshold volume of cystometries performed during one hour before and each hour after the stimulation were compared., Results: After six periods of IVES, the micturition threshold volume decreased to its lowest value (62% of control) during the first hour and remained at 80% 4 h later (n = 10, P < 0.01). Ano-genital afferent stimulation produced a corresponding increase in the micturition threshold volume. The long-lasting poststimulation effect was again observed for more than 5 h. During the first hour the mean threshold volume increased to 211% of controls and it remained at about this level for the entire observation period (n = 8, P < 0.01)., Conclusions: Repeated short periods of stimulation prolonged the modulatory effect well beyond the stimulation period. The findings provide experimental evidence supporting the clinical application of IVES and ano-genital stimulation for treatment of neurogenic urinary bladder dysfunction., (© 2018 Wiley Periodicals, Inc.)

Aims: Experimental animal models of bladder outlet obstruction (BOO) have reproduced several features of BOO in man, i.e., detrusor hypertrophy, instability, frequency, and residual urine. This study was focused on the mechanisms underlying the development of residual urine in patient with benign prostatic hyperplasia (BPH) by examining changes in tension sensitivity of bladder mechanoreceptors in rat model., Methods: Female adult Sprague-Dawley rats including 12 BOO and 17 sham operated rats were used in this study. Cystometrograms together with the bladder afferent activity were recorded. Tension sensitivity of the afferents was determined by plotting the normalized afferent response against the contraction evoked bladder pressure at different volumes. Degree of obstruction was assessed by the wet weight of the bladder at the end of the experiment., Results: The bladder weight, maximal bladder capacity, micturition threshold volume, peak contraction force, and volume at peak contraction force were all significantly increased in obstructed animals. The threshold volume for afferent activation was increased (mean 0.60 ml compared to 0.15 ml in controls; P < 0.001), positively correlated with the bladder weight (r = 0.74). The tension sensitivity of the bladder mechanoreceptors and the slope of their normalized pressure-response functions were significantly lower at the comparable volumes in the obstructed animals., Conclusions: Rats with BOO had bladder mechanoreceptors with higher threshold volumes and lower tension sensitivity. Such changes would result in a weaker afferent drive of the micturition reflex. Similar changes may contribute to the development of residual urine and retention in patients with BOO., (Copyright © 2011 Wiley Periodicals, Inc.)

Aims: To determine whether C afferents can modify the gating of the Adelta micturition reflex in order to identify the neuronal site of interaction of the two afferent systems., Methods: Adult female cats, anaesthetized with alpha-chloralose, had their bladder and urethra catherized through a slit in the proximal urethra. Micturition threshold volume was assessed by cystometry and bladder efferent activity recorded simultaneously. The bladder was filled at a slow rate (1.2-3.5 ml/min) with either body-warm saline (control) or menthol solution (0.06 mM) or by cold saline (4 degrees C)., Results: Of 14 trial sessions in 5 animals, the threshold volume of the Adelta micturition reflex was consistently reduced by menthol infusions from a control median (md) value of 16.8 to 10.2 ml (P < 0.01). The threshold pressure was also somewhat decreased from md 0.7 to 0.5 kPa (P < 0.05), while the peak pressure or pressure slope did no differ in two situations. Similar results were obtained with slow cold infusions into the bladder (nine sessions in three animals). The threshold volume decreased from md 19.8 to 17.4 ml (P < 0.05). The bladder reflex response to slow menthol or cold infusions had the typical features of an Adelta micturition reflex in that the efferent activity was largely abolished by the bladder Adelta mechanoreceptor unloading., Conclusions: Gradual tonic activation of bladder cold receptors lowers the threshold volume of the ordinary Adelta micturition, pointing to a segmental spinal mechanism for the gating of the micturition reflex., ((c) 2009 Wiley-Liss, Inc.)

Aims: To evaluate the results of intravesical electrical stimulation (IVES) in an open prospective study to treat underactive detrusor in children. The treatment was offered as an alternative to clean intermittent catheterization (CIC)., Methods: Forty-four children were included, 21 girls and 3 boys (6-16 years, md 10) with idiopathic, 9 girls and 11 boys (4-18 years; md 13) with neurogenic underactive detrusor. IVES was given by a catheter electrode in the bladder (cathode) with the anode attached to the suprapubic abdominal skin. Continuous stimulation at 20 or 25 Hz was delivered by battery powered stimulators giving unipolar square-wave pulses (0,2 or 0,7 ms). Stimulation intensity was adjusted individually according to the acceptance of the child (12-64 mA). IVES was initially given at the clinic but 18 children had additional treatment at home. Effect of treatment was monitored by micturiton/incontinence diary, reports of bladder sensation, recordings of urinary flow, residual volume and frequency of urinary tract infections., Results: The IVES-treatment was completed by 39/44 children. Long term normalization of the voiding (md 2,5 years follow up) was obtained for 20/24 children with idiopathic problems (83%) and 8/20 with neurogenic problems (40%). Another four had much improved bladder function. The neurogenic group required more stimulation sessions than the idiopathic group. Of those on CIC, 11/15 who completed IVES could discontinue the catheterization. The frequency of urinary tract infections and incontinence decreased significantly (P < 0.01)., Conclusions: It is concluded that IVES is a promising method to treat the underactive detrusor in children., (Copyright 2003 Wiley-Liss, Inc.)

Pelvic floor training is an established conservative method of treatment in patients with genuine stress incontinence. It is not known why only a proportion of patients benefit from this form of treatment, while others with a comparable degree of incontinence do not. Since muscle awareness is of vital importance in pelvic floor training, we decided to investigate whether differences in outcome might be explained by differences in cortical control of the pelvic floor muscles. The function in the total motor pathway to the pelvic floor muscles was examined with cortical magnetic stimulation and circumvaginal EMG recording. Since lesions of the peripheral motor pathway have been demonstrated in patients with genuine stress incontinence, possible differences at this level were investigated by means of terminal pudendal motor latencies, using electrical nerve stimulation and anal recording EMG. We found that patients who succeeded with pelvic floor exercises for genuine stress incontinence had a significantly higher probability of response to cortical magnetic stimulation and significantly larger response amplitudes than the patients who did not benefit from training. The findings in the latter group did not differ from those of a healthy control group. No differences between the groups were found in the terminal pudendal motor latencies. We conclude that women with genuine stress urinary incontinence, successfully alleviated by a physiotherapeutic training program, have a higher degree of corticofugal control of their perineal muscles than women who do not succeed with the same treatment program and healthy controls. Neurourol. Urodynam. 18:437-445, 1999., (Copyright 1999 Wiley-Liss, Inc.)

Based on a large retrospective series, this study compares the International Continence Society's (ICS) classification of overactive bladders and a functional subtyping of our own, founded on clinical and urodynamic parameters. Functionally identical symptoms and urodynamic patterns were found within the Detrusor Hyperreflexia as well as the Unstable Detrusor categories. There are strong arguments for a revision of the current ICS classification system.