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The therapeutic effect of doxazosin (40 μg/kg/day over one month) on urinary bladder was examined in female rats with modeled chronic infravesical obstruction (IVO) produced by graduated mechanical constriction of the proximal urethral segment. In one month, IVO induced a pronounced vesical hypertrophy both in treated and untreated rats that manifested in increased bladder weight and capacity, the latter increment being pronouncedly greater in treated rats. In untreated IVO rats, infusion cystometry revealed elevated basal intravesical pressure of void bladder P 0 , markedly increased maximal (premicturitional) pressure P max , and increased amplitude of spontaneous oscillations of intravesical pressure ΔP det in filled bladder. Doxazosin produced no significant effect on P max rise during IVO, but prevented elevation of P 0 and increment of ΔP det in filled bladder. During gradual filling of urinary bladder in control (intact) rats, the parasympathetic vesical influences increased progressively, while in untreated IVO rats, the adrenergic influences prevailed even at maximal filling of the bladder. In IVO rats, doxazosin prevented the bias of the sympathetic-parasympathetic balance in the filled bladder in favor of sympathetic influences, but did not prevent this bias in a void bladder. It is hypothesized that α-adrenoblockers improve micturition during IVO caused by benign prostatic hyperplasia not only by decreasing the urethral resistance to urine flow due to down-regulation of prostate smooth muscle tone, but also by a direct action of these blockers on detrusor adrenergic receptors and central structures involved in urinary bladder control.

Purpose: To evaluate the effect of pentoxifylline (PTX), a nonspecific type 4 phosphodiesterase inhibitor, on contractility of obstructed detrusor muscles., Methods: Sixty male Sprague-Dawley rats were randomized into three groups each containing 20 animals. The control groups included rats with induced BOO which received the solvent of PTX (drinking water), the sham group included rats with intact bladder outlet which received no treatment, and the treatment group was treated with PTX after induction of BOO. Four weeks after the operation and/or treatment, animals were killed and detrusor muscle of them was evaluated for contractility parameters., Results: Carbachol-induced detrusor muscle tension increased proportionally with concentration of carbachol. The maximum carbachol-inducing muscle tension was significantly higher in the sham group in comparison to the rats with BOO (P < 0.001). In the latter group, PTX treatment caused no significant improvement in the maximum carbachol-induced muscle tension compared to the control group. However, no significant difference was observed among the study groups concerning the pEC50 of carbachol (5.77 ± 0.10, 5.96 ± 0.64, and 5.84 ± 0.17 in the sham, control, and treatment groups, respectively). BOO resulted in a great but statistically non-significant (P = 0.074) decrease in electrically induced bladder contraction in comparison with the sham group. Treatment with PTX reversed this effect significantly (P = 0.023), and the obtained values were almost the same as those of the sham group., Conclusion: PTX improved detrusor muscle contractions in responses to electric stimulation in obstructed bladder. In contrast, no improvement was detected in contractile responses to the carbachol stimulation.

Introduction and Hypothesis: The purpose of this study was to evaluate the predictors of de novo stress urinary incontinence (SUI) in patients undergoing a tension-free vaginal mesh procedure (TVM) for pelvic organ prolapse (POP)., Methods: Sixty-five patients without SUI were assessed with regard to voiding function by a pressure flow study and clinical characteristics., Results: The mean age of the patients was 67 ± 8.3. Of the 65 patients, 41 (63 %) maintained urinary continence postoperatively and 24 (37 %) showed de novo SUI. In univariate analysis, the de novo SUI group included a significantly higher proportion of patients with preoperative obstruction, defined as moderate or greater obstruction according to the Blaivas nomogram (29 vs 7 %, P = 0.035). In multivariate analysis, urethral obstruction was an independent predictor of de novo SUI with an odds ratio of 12.616 (95 % confidence interval 1.580-268.731)., Conclusions: Preoperative evaluation of urethral obstruction will contribute to prediction of de novo SUI combined with a conventional diagnosis of occult SUI.

Introduction and Hypothesis: Iatrogenic female urethral obstruction resulting from sling operations may be related to surgical inexperience and must be better understood. Although there are no widely recognized parameters for this type of study, a single-surgeon consecutive series offers an opportunity to study the role of expertise in sling operations over time., Methods: This study consecutively examined 176 women who underwent an autologous fascial sling procedure. Postoperative urethral obstruction was identified by the occurrence of voiding dysfunctions. Clinically obstructed patients were invited to undergo a postoperative urodynamic evaluation after 3 months. To enable comparison, patients were placed into 6-month groups according to the time of surgery., Results: A total of 159 cases were evaluated with a mean follow-up time of 32.4 ± 13.4 months. Stress continence was cured in 97.5% of cases. Although 29 patients were identified as obstructed, only 20 underwent a postoperative urodynamic evaluation. Only five of the clinically obstructed cases showed a high P(det)Q(max). All of the other cases met one or more of the non-classic parameters linked to obstruction. Overactive bladder was present in 14 (63.6%) of the obstructed cases. Iatrogenic urethral obstruction was more common among the early cases (30.4%) than among the later ones (5%) (P < 0.001). Postoperative urodynamic evaluation showed a trend toward obstruction on pressure flow studies., Conclusions: Autologous fascial sling operations require expertise and involve a clear surgical learning curve. Iatrogenic obstruction in females does not fit a single model and may be difficult to recognize. Obstruction in females must be identified through clinical indicators and postoperative urinary complaints rather than the high detrusor pressure observed in men. Furthermore, iatrogenic female obstruction can probably be minimized but not eliminated.

Introduction and Hypothesis: We compared pre- and postoperative voiding function in patients with POP and assessed the efficacy of urodynamic studies in these cases., Methods: Forty-six patients treated with the tension-free vaginal mesh (TVM) procedure between January 2009 and February 2010 underwent pressure flow study pre- and postoperatively. Pre- and postoperative voiding functions were assessed according to Schäfer nomograms., Results: The mean postoperative detrusor pressure at maximal flow was decreased significantly compared with that preoperatively. The mean maximum flow rate was also improved significantly and the proportion of normal contractility was increased significantly after the operation, as was the proportion of non-obstructive patients., Conclusions: The TVM procedure for pelvic organ prolapse improved both detrusor contractility and urethral obstruction.

Background: Overactivity of the detrusor due to benign prostatic hyperplasia may be induced by hyperpermeability of the smooth muscle cell membrane to calcium. We investigated the effect of verapamil, a calcium channel blocker, on detrusor function in outflow obstructed and control rat bladders., Methods: Verapamil was injected intravenously via a catheter inserted into the internal jugular vein in doses of 0.5, 1.0, 2.0, 4.0, and 10.0 mg/kg in rat bladders with and without partial outflow obstruction under urethane anaesthesia. The intravesical pressure was monitored continuously. We measured the tidal voided urine volume, the voiding pressure, the pressure at which micturition was induced, and the end-point pressure of micturition., Results: The tidal voided urine volume was significantly decreased in the obstructed bladders before administration of verapamil. Verapamil had similar effects in cystometric parameters in obstructed and control bladders. Verapamil increased the tidal voided urine volume, the pressure at which micturition was induced, and the end-point pressure of micturition, and reduced the voiding in obstructed and control bladders. Verapamil at doses of 4.0 mg/kg or higher induced significant arrhythmia., Conclusions: Verapamil reduced the contractile force of the bladder and increased the capacity and residual urine volume in both normal and obstructed bladders. Thus, although calcium channel blockers such as verapamil may be effective in treating a hyperactive bladder, they may have adverse cardiovascular effects.

In the rabbit, partial outlet obstruction of the urinary bladder results in significant changes in the physiology, cellular structure, and cellular metabolism of that organ. One of the most striking changes observed is a 50% decrease in oxidative metabolism. Here we investigate whether the function of the mitochondrial (mt) genetic system is altered in rabbit bladder tissue following partial outlet obstruction. Southern analyses of total DNA prepared from bladder tissue excised as a function of time after initiation of partial outlet obstruction showed that the relative number of copies of the mt genome decreases as much as 10-fold during the first 7 d after obstruction, and that this attenuated mt genome copy number is maintained until at least 14 d post-obstruction. Northern analyses, in contrast, showed that mt COII and cytochrome b transcript levels initially decrease but recover to control levels by about 5 d after obstruction; that level is maintained through 14 d post-obstruction. Enzymatic analysis of cytochrome oxidase and NADH cytochrome c reductase activities in obstructed bladder tissue gave results which paralleled the pattern in the mt RNA analyses. Surprisingly, transcript levels for the mt-related nuclear COIV gene rapidly decreased to about 50% of control levels following obstruction and remained there until 14 d post-obstruction. These results indicate that partial outlet obstruction of the rabbit bladder leads to significant changes in the status and expression of the mt genetic system in bladder tissue.(ABSTRACT TRUNCATED AT 250 WORDS)

When urethral flow is treated as a lossless flow through an elastic tube, the relationship between the detrusor pressure and the urinary flow can be related to the elasticity of the flow-controlling zone of the urethra. A recent analytical method of describing urethral elasticity is implemented on a computer. The function p(Q) = pmo + LmQm is fitted to the recorded pressure/flow data. p(Q) is the detrusor pressure, Q the flow and pmo, m and Lm parameters. The elastic properties are then obtained as p(A) = pmo + KnAn, where p(A) is the static pressure, A the cross-sectional area of the flow-controlling zone and n and Kn calculated parameters. The urodynamic methods used and the computer implementation of the analytical method are described. In obstructed and unobstructed men without neurological symptoms, the elastic properties could be estimated in 94 per cent of the micturitions. The method makes it possible to describe urethral flow properties with Griffiths' model in a standardised way and compare results obtained by different investigators. It is recommended for quantification of urethral obstruction in research and for assessment of borderline cases of obstruction in clinical practice.

Urethral destruction is only occasionally the reason for prostatitis and Cowperitis and prostatitis is only demonstrated occasionally to complicate urethral stricture. It is a dependence of prostatitis and spastic urethral obstruction in the neuropathic bladder.