Neural control of the urethra and development of pharmacotherapy for stress urinary incontinence

Urethral dysfunction in a rat model of chemically induced prostatic inflammation: potential involvement of the MRP5 pump

Prostate inflammation (PI) is a clinical condition associated with infection and/or inflammation of the prostate. It is a common disease frequently associated to lower urinary tract (LUT) symptoms. The urethra is an understudied structure in the LUT and plays a fundamental role in the urinary cycle. Here, we proposed to evaluate the effect of PI on the urethra tissue. Male Sprague-Dawley rats were used, and PI was induced by formalin injection into the ventral lobes of the prostate. The pelvic urethra at the prostatic level was harvested for histological analysis, contraction (electrical field stimulation and phenylephrine), and relaxation (sodium nitroprusside/MK-571) experiments. Various gene targets [cytochrome c oxidase subunit 2, transforming growth factor-β₁, interleukin-1β, hypoxia-inducible factor-1α, α_1A-adrenoceptor, inositol 1,4,5-trisphosphate receptor type 1, voltage-gated Ca²⁺ channel subunit-α_1D, neuronal nitric oxide synthase, soluble guanylyl cyclase, phosphodiesterase 5A, protein kinase CGMP-dependent 1, and multidrug resistance-associated protein 5 (MRP5; ATP-binding cassette subfamily C member 5)] were quantified, and cGMP levels were measured. No histological changes were detected, and functional assays revealed decreased contraction and increased relaxation of urethras from the PI group. The addition of MK-571 to functional assays increased urethral relaxation. Genes associated with inflammation were upregulated in urethras from the PI group, such as cytochrome oxidase c subunit 2, transforming growth factor-β₁, interleukin-1β, and hypoxia-inducible factor-1α. We also found increased expression of L-type Ca²⁺ channels and the neuronal nitric oxide synthase enzyme and decreased expression of the MRP5 pump. Finally, cGMP production was enhanced in urethral tissue of PI animals. The results indicate that PI is associated with proinflammatory gene expression in the urethra without histologically evident inflammation and that PI produces a dysfunctional urethra and MRP5 pump downregulation, which results in cGMP accumulation inside the cell. These findings would help to better understand LUT dysfunctions associated with PI and the role of MRP pumps in the control of LUT function.

Inhibition of Multidrug Resistance Proteins by MK 571 Enhances Bladder, Prostate, and Urethra Relaxation through cAMP or cGMP Accumulation

The biologic effect of cAMP and cGMP is terminated by phosphodiesterases and multidrug resistance proteins MRP4 and MRP5, which pump cyclic nucleotides out of the cell. Therefore, this study aimed to characterize the role of MRP inhibitor, MK 571 (3-[[[3-[(1E)-2-(7-chloro-2-quinolinyl)ethenyl]phenyl][[3-(dimethylamino)-3-oxopropyl]thio]methyl]thio]propanoic acid), in the bladder, prostate, and urethra of male mice by means of functional assays, protein expression, and cyclic nucleotide quantification. The cumulative addition of MK 571 (1-30 µM) produced only small relaxation responses (approximately 25%) in all studied tissues. In the bladder, isoprenaline/fenoterol and forskolin concentration-dependently relaxed and MK 571 (20 µM) increased the maximal response values by 37% and 24%, respectively. When MK 571 was coincubated with fenoterol or forskolin, intracellular levels of cAMP and protein expression of phospho-vasodilator-stimulated phosphoprotein (p-VASP) Ser157 were significantly greater compared with bladders stimulated with fenoterol or forskolin alone. In the prostate and urethra, sodium nitroprusside concentration-dependently relaxed and MK 571 (20 µM) significantly increased relaxation responses by 70% and 56%, respectively, accompanied by greater intracellular levels of cGMP and protein expression of p-VASP Ser239 in the prostate. Tadalafil and BAY 41-2272 (5-cyclopropyl-2-[1-[(2-fluorophenyl)methyl]-1H-pyrazolo[3,4-b]pyridin-3-yl]-4-pyrimidinamine) also relaxed the prostate and urethra, respectively, and MK 571 markedly enhanced this response. The stable analog of cGMP (8-Br-cGMP) induced concentration-dependent relaxation responses in the prostate and urethra, and MK 571 significantly increased the relaxation response. In conclusion, to our knowledge, this is the first study to show that efflux transporters are physiologically active in the bladder, prostate, and urethra to control intracellular levels of cAMP or cGMP.

Receptor and transporter binding and activity profiles of albiflorin extracted from Radix paeoniae Alba

Albiflorin, a traditional Chinese herb, is a main component of Radix paeoniae Alba, which has been used for the treatment of depressive disorders since ancient times. However, the mechanism of the antidepressant effect of albiflorin is poorly understood. Thus, we explored the binding profile of albiflorin at neurotransmitter receptors and transporters. We also characterised the in vivo effect of albiflorin on monoaminergic systems by using microanalysis to determine the extracellular levels of serotonin (5-HT) and norepinephrine (NE) in the hypothalamus of freely moving rats administered albiflorin. We found that albiflorin inhibited the uptake of 5-HT and NE and displayed robust binding affinities for the transporters of both neurotransmitters. By contrast, albiflorin (10 μM) showed no significant affinity to a wide array of central nervous system receptors. The results of our in vivo microdialysis studies showed that administration of albiflorin (3.5, 7.0, 14.0 mg/kg) significantly increased extracellular concentrations of 5-HT and NE in the hypothalamus of freely moving rats. Overall, the current study showed that albiflorin is a novel 5-HT and NE reuptake inhibitor with high selectivity.

Soluble guanylyl cyclase (sGC) degradation and impairment of nitric oxide-mediated responses in urethra from obese mice: reversal by the sGC activator BAY 60-2770

Obesity has emerged as a major contributing risk factor for overactive bladder (OAB), but no study examined urethral smooth muscle (USM) dysfunction as a predisposing factor to obesity-induced OAB. This study investigated the USM relaxant machinery in obese mice and whether soluble guanylyl cyclase (sGC) activation with BAY 60-2770 [acid 4-({(4-carboxybutyl) [2-(5-fluoro-2-{[4-(trifluoromethyl) biphenyl-4-yl] methoxy} phenyl) ethyl] amino} methyl) benzoic] rescues the urethral reactivity through improvement of sGC-cGMP (cyclic guanosine monophosphate) signaling. Male C57BL/6 mice were fed for 12 weeks with a high-fat diet to induce obesity. Separate groups of animals were treated with BAY 60-2770 (1 mg/kg per day for 2 weeks). Functional assays and measurements of cGMP, reactive-oxygen species (ROS), and sGC protein expression in USM were determined. USM relaxations induced by NO (acidified sodium nitrite), NO donors (S-nitrosoglutathione and glyceryl trinitrate), and BAY 41-2272 [5-cyclopropyl-2-[1-(2-fluoro-benzyl)-1H-pyrazolo[3,4-b]pyridin-3-yl]-pyrimidin-4-ylamine] (sGC stimulator) were markedly reduced in obese compared with lean mice. In contrast, USM relaxations induced by BAY 60-2770 (sGC activator) were 43% greater in obese mice (P < 0.05), which was accompanied by increases in cGMP levels. Oxidation of sGC with ODQ [1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one] (10 μM) potentiated BAY 60-2770-induced USM responses in the lean group. Long-term oral BAY 60-2770 administration fully prevented the impairment of USM relaxations in obese mice. Reactive-oxygen species (ROS) production was enhanced, but protein expression of β1 second guanylate cyclase subunit was reduced in USM from obese mice, both of which were restored by BAY 60-2770 treatment. In conclusion, impaired USM relaxation in obese mice is associated with ROS generation and down-regulation of sGC-cGMP signaling. Prevention of sGC degradation by BAY 60-2770 ameliorates the impairment of urethral relaxations in obese mice.

Urinary incontinence and diarrhoea associated with the switch from oral to injectable risperidone

OBJECTIVE

Urgency, urinary incontinence and bowel disturbances are distressing side effects that have been observed during treatment with risperidone and other antipsychotics probably due to the receptor affinity profile. This occurrence can lead to poor compliance and therefore impair clinical outcome.

METHOD

We report the case of a 50 year-old lady, who experienced urinary incontinence and diarrhoea, when switching from oral to injectable risperidone, which ceased when discontinuing the drug. Results and conclusions It should be taken into account that some side effects can be revealed when switching from oral to depot formulations due to non-compliance to orals; nevertheless dose-dependent mechanisms and individual metabolic variability must be considered when observing idiosyncratic reactions to drugs.

Nuclear expression of PG-21, SRC-1, and pCREB in regions of the lumbosacral spinal cord involved in pelvic innervation in young adult and aged rats

In rats, ageing results in dysfunctional patterns of micturition and diminished sexual reflexes that may reflect degenerative changes within spinal circuitry. In both sexes the dorsal lateral nucleus and the spinal nucleus of the bulbospongiosus, which lie in the L5-S1 spinal segments, contain motor neurons that innervate perineal muscles, and the external anal and urethral sphincters. Neurons in the sacral parasympathetic nucleus of these segments provide autonomic control of the bladder, cervix and penis and other lower urinary tract structures. Interneurons in the dorsal gray commissure and dorsal horn have also been implicated in lower urinary tract function. This study investigates the cellular localisation of PG-21 androgen receptors, steroid receptor co-activator one (SRC-1) and the phosphorylated form of c-AMP response element binding protein (pCREB) within these spinal nuclei. These are components of signalling pathways that mediate cellular responses to steroid hormones and neurotrophins. Nuclear expression of PG-21 androgen receptors, SRC-1 and pCREB in young and aged rats was quantified using immunohistochemistry. There was a reduction in the number of spinal neurons expressing these molecules in the aged males while in aged females, SRC-1 and pCREB expression was largely unchanged. This suggests that the observed age-related changes may be linked to declining testosterone levels. Acute testosterone therapy restored expression of PG-21 androgen receptor in aged and orchidectomised male rats, however levels of re-expression varied within different nuclei suggesting a more prolonged period of hormone replacement may be required for full restoration.

Neurophysiology and therapeutic receptor targets for stress urinary incontinence

Stress urinary incontinence is the most common type of urinary incontinence in women. Stress urinary incontinence involves involuntary leakage of urine in response to abdominal pressure caused by activities, such as sneezing and coughing. The condition affects millions of women worldwide, causing physical discomfort as well as social distress and even social isolation. This type of incontinence is often seen in women after middle age and it can be caused by impaired closure mechanisms of the urethra as a result of a weak pelvic floor or poorly supported urethral sphincter (urethral hypermobility) and/or a damaged urethral sphincter system (intrinsic sphincter deficiency). Until recently, stress urinary incontinence has been approached by clinicians as a purely anatomic problem as a result of urethral hypermobility requiring behavioral or surgical therapy. However, intrinsic sphincter deficiency has been reported to be more significantly associated with stress urinary incontinence than urethral hypermobility. Extensive basic and clinical research has enhanced our understanding of the complex neural circuitry regulating normal function of the lower urinary tract, as well as the pathophysiological mechanisms that might underlie the development of stress urinary incontinence and lead to the development of potential novel strategies for pharmacotherapy of stress urinary incontinence. Therapeutic targets include adrenergic and serotonergic receptors in the spinal cord, and adrenergic receptors at the urethral sphincter, which can enhance urethral reflex activity during stress conditions and increase baseline urethral pressure, respectively. This article therefore reviews the recent advances in stress urinary incontinence research and discusses the neurophysiology of urethral continence reflexes, the etiology of stress urinary incontinence and potential targets for pharmacotherapy of stress urinary incontinence.

Urinary incontinence: pharmacotherapy options

The impact of incontinence is felt by millions of people worldwide, with tremendous decrement in quality of life and enormous cost reaching billions of dollars. Urinary incontinence is defined as 'involuntary leakage of urine' and is categorized into two main types: urgency urinary incontinence (UUI) and stress urinary incontinence (SUI). Behavioral modifications and pharmacologic therapies, primarily antimuscarinic agents, are the mainstay of treatment for UUI. These drugs are moderately efficacious but have troublesome side-effects, the combination resulting in poor compliance and persistence with therapy. There are several agents on the market today, each with some variation in pharmacologic properties. Whether these translate into meaningful differences in clinical efficacy and tolerability remains a matter of debate. Treatment of SUI has seen little success with pharmacologic therapy. In Europe, duloxetine is approved for treatment of SUI with marginal success rates; this drug, although available in the United States for treatment of depression, is not approved for SUI. The search for newer and better pharmacologic options and novel therapies is on-going, fueled primarily by the high prevalence of bothersome incontinence and the tremendous number of health care dollars spent on current therapy. This review addresses pharmacologic options for treatment of urinary incontinence.

Neurophysiology of the lower urinary tract

The lower urinary tract (LUT) has two functions: (1) the storage of waste products in the form of urine and (2) the elimination of those wastes through micturition. The LUT operates in a simple "on-off" fashion, either storing urine or releasing it during voiding. While this activity may seem simple, micturition is controlled by a complex set of peripheral neurons that are, in turn, coordinated by cell groups in the spinal cord, brainstem, and brain. When this careful coordination is interrupted, the control of the bladder is lost, resulting in incontinence or retention of urine. The purpose of this chapter is to review how the neural systems coordinating the activity of the lower urinary tract form neural circuits that are responsible for either maintaining continence (the storage reflex) or inducing micturition (the voiding reflex). We will also discuss the brain centers that enable higher organisms to voluntarily choose the time and place for voiding. Finally, we will discuss how defects in the pathways controlling micturition can lead to urinary incontinence and which treatments may normalize LUT function.

Pharmacologic management of urinary incontinence, voiding dysfunction, and overactive bladder

Most drugs used in the treatment of urinary incontinence and voiding dysfunction in women modulate neuromuscular transmission in the urethra and bladder. Pharmacotherapy is the mainstay of treatment for overactive bladder. Although several different antimuscarinic medications are available for the treatment of overactive bladder, most have similar efficacy and tolerability. Pharmacotherapy has a limited role in the management of stress incontinence and voiding dysfunction in women. Newer drugs that target different mechanisms of action are being developed for the treatment of urinary incontinence and voiding dysfunction in women.

Involvement of reflex urethral closure mechanisms in urethral resistance under momentary stress condition induced by electrical stimulation of rat abdomen

A novel method for evaluating the urethral resistance during abrupt elevation of abdominal pressure was developed in spinalized female rats under urethane anesthesia. Electrical stimulation of abdominal muscles for 1 s induced increases in both the intra-abdominal and the intravesical pressure in a stimulus-dependent manner, and the bladder response was almost lost when the abdomen was opened. The lowest intravesical pressure during electrical stimulation that induced fluid leakage from the urethral orifice (leak point pressure) and the maximal intravesical pressure without urine leakage below the leak point pressure were evaluated as the indexes of urethral resistance. Lower urethral resistance was obtained in the rats whose pelvic nerves or somatic nerves containing pudendal nerves and nerves to iliococcygeus/pubococcygeus muscles were transected bilaterally. In contrast, transection of bilateral hypogastric nerves showed smaller effects. Duloxetine, a drug for stress urinary incontinence, enlarged the reflex urethral closing contractions that were induced by an increase in intravesical pressure and measured using a microtip transducer catheter in the middle urethra. This drug also increased the urethral resistance (leak point pressure), whereas it did not show any effect in the rats whose pelvic nerves were bilaterally transected, showing that the augmentation of the reflex urethral closure by the drug resulted in the elevation of the urethral resistance. From these findings, it was concluded that during momentary elevation of abdominal pressure, the reflex urethral closure mechanisms via bladder-spinal cord-urethral sphincter and pelvic floor muscles greatly contribute to the increase in the urethral resistance to prevent the urinary incontinence.

Self-harm and depression in women with urinary incontinence: a record-linkage study

OBJECTIVE

To investigate the association between self-harm and urinary incontinence (UI), and between depression and UI, in women.

PATIENTS AND METHODS

The incidence of self-harm in women with UI is not well documented. We analysed a statistical database that includes hospital contact data for UI and for self-harm and depression. We calculated rate ratios for self-harm and depression in a cohort of women admitted for UI, and rate ratios for UI in cohorts of women admitted with self-harm or depression, compared with a control cohort.

RESULTS

After admission for UI, self-harm was significantly high in young women (aged < 45 years: rate ratio 1.73, 95% confidence intervals 1.37-2.14) but not in older women. Depression was associated with UI in all age groups, e.g. after admission for depression the rate ratio for UI within 5 years was 1.46 (1.33-1.75); and for UI at > or = 5 years after admission for depression, it was 1.20 (1.05-1.35).

CONCLUSIONS

Young women with UI are at risk of self-harm. For all age groups studied, depression was more common in women with UI than in others. Depression might be a consequence of UI, but the increase in risk at long intervals before admission with UI suggests that they might share underlying causal mechanisms.

The striated urethral sphincter of the pig shows morphological and functional characteristics essential for the evaluation of treatments for sphincter insufficiency

PURPOSE

New treatments are currently under investigation for intrinsic sphincter insufficiency. However, animal models in which to study the resting urethral tone generated by the striated urethral sphincter are still lacking. We describe the striated urethral sphincter in the pig. We investigated its participation in resting urethral tone with the aim of developing new tools for evaluating therapies for sphincter insufficiency.

MATERIALS AND METHODS

A total of 15 female pigs were used in this study. Anatomy of the striated urethral sphincter was described via transpubic and endoscopic approaches. Participation of the striated urethral sphincter in resting urethral tone was assessed by analysis of urethral pressure profilometry (maximum urethral closure pressure, functional urethral length and area under the curve) before and after curare injection or by destruction of the striated urethral sphincter by endoscopic electrocautery. Serial urethral cross sections were immunostained for slow/fast myosin and digitalized for 3-dimensional reconstructions to determine striated urethral sphincter volume.

RESULTS

The striated urethral sphincter was Omega-shaped and it encircled the distal third of the urethra. A mean peak intraurethral pressure +/- SEM of 58.9 +/- 13.4 cm H(2)O was noted in front of the striated urethral sphincter. Curare injection and endoscopic injury decreased maximum urethral closure pressure by 48.4% and 51.1%, functional urethral length by 10.3% and 15.3%, and area under the curve by 47% and 64%, respectively. The striated urethral sphincter consisted of 52% slow and 48% fast myofibers. Its mean volume was 0.87 cm.

CONCLUSIONS

The striated urethral sphincter of the female pig shows the morphological and functional features of a tonic muscle. Methods of measuring resting urethral tone generated by the striated urethral sphincter represent original tools for evaluating therapies for intrinsic sphincter insufficiency.

The effects of ageing on the distribution of vesicular acetylcholine transporter immunoreactive inputs to pelvic motoneurons of male Wistar rats

Age-related changes in the number and size of large cholinergic terminals immunoreactive for vesicular acetylcholine transporter (VAChT), were documented for the dorsolateral nucleus (DLN), retrodorsolateral nucleus (RDLN) and spinal nucleus of the bulbospongiosus (SNB) of the lumbosacral spinal cord of male rats. The most significant changes were a large increase in the number and size of cholinergic terminals within the DLN of aged animals, together with a small decrease in terminal number within the RDLN. No significant age-associated differences in VAChT labeling were seen within the SNB. In both age groups, SNB motoneurons projecting to the levator ani muscle received about 9 to 10 contacts from large cholinergic terminals. Ultrastructural examination of the terminals revealed structures likely to be postsynaptic subsurface cisterns that are characteristic of type C terminal boutons. Since both the DLN and SNB contain motoneurons innervating pelvic muscles and sphincters, these findings provide further evidence for a central cholinergic influence on micturition and sexual reflexes and suggest that this may remain robust in the face of ageing.

Desvenlafaxine succinate: A new serotonin and norepinephrine reuptake inhibitor

The purpose of this study was to characterize a new chemical entity, desvenlafaxine succinate (DVS). DVS is a novel salt form of the isolated major active metabolite of venlafaxine. Competitive radioligand binding assays were performed using cells expressing either the human serotonin (5-HT) transporter (hSERT) or norepinephrine (NE) transporter (hNET) with K(i) values for DVS of 40.2 +/- 1.6 and 558.4 +/- 121.6 nM, respectively. DVS showed weak binding affinity (62% inhibition at 100 microM) at the human dopamine (DA) transporter. Inhibition of [3H]5-HT or [3H]NE uptake by DVS for the hSERT or hNET produced IC50 values of 47.3 +/- 19.4 and 531.3 +/- 113.0 nM, respectively. DVS (10 microM), examined at a large number of nontransporter targets, showed no significant activity. DVS (30 mg/kg orally) rapidly penetrated the male rat brain and hypothalamus. DVS (30 mg/kg orally) significantly increased extracellular NE levels compared with baseline in the male rat hypothalamus but had no effect on DA levels using microdialysis. To mimic chronic selective serotonin reuptake inhibitor treatment and to block the inhibitory 5-HT(1A) autoreceptors, a 5-HT(1A) antagonist, N-[2-[4-(2-methoxyphenyl)-1-piperazinyl]ethyl]-N-2-pyridinylcyclo hexanecarboxamide maleate salt (WAY-100635) (0.3 mg/kg s.c.), was administered with DVS (30 mg/kg orally). 5-HT increased 78% compared with baseline with no additional increase in NE or DA levels. In conclusion, DVS is a new 5-HT and NE reuptake inhibitor in vitro and in vivo that demonstrates good brain-to-plasma ratios, suggesting utility in a variety of central nervous system-related disorders.

The Rationale of Dual Serotonin/Noradrenaline Reuptake Inhibitors in the Management of Stress Urinary Incontinence

This paper aims at evaluating the role of serotonin (5-HT) and noradrenaline in the nervous control of urinary continence. Both α1-adrenergic and 5-HT2 receptors in the Onuf's nucleus help the guarding reflex; therefore the pharmacologic agents enhancing the effects of 5-HT and noradrenaline represent a promising choice in treating stress urinary incontinence. Duloxetine, a dual 5-HT/noradrenaline reuptake inhibitor, improves the external urethral sphincter contractility while increasing the activation of 5-HT2 and α1-adrenergic receptors thanks to the high concentrations of these monoamines in the Onuf's nucleus; it also plays a significant role in the management of stress urinary incontinence.

Abdominal muscle activity during voiding in female rats with normal or irritated bladder

The aims of the present study were to determine in female rats whether abdominal muscle discharges during normal voiding and to describe the effect of bladder irritation on this visceromotor activity. The sensory pathway of this reflex was also determined. Electromyograms (EMGs) indicated that in awake rats, the abdominal muscle was consistently activated during spontaneous voiding and during voiding induced by saline infusion. Similarly, in anesthetized animals, the muscle discharged during urine expulsion. The abdominal EMG activity was not abolished by hypogastric (Hgnx) or sensory pudendal neurectomy (SPdnx). SPdnx dramatically decreased the intercontraction interval and voided volume. Acetic acid infusion reduced the intercontraction interval and increased bladder contraction duration. It also reduced the pressure threshold for evoking the abdominal EMG response and increased the EMG duration and amplitude. Although SPdnx and Hgnx modified some urodynamic parameters, they did not reverse the acetic acid effect on EMG activity. Thus the afferents activating the visceromotor reflex during normal voiding and the increased reflex in response to acetic acid are probably both carried by the pelvic nerve. Abdominal muscle activity induced by bladder distension has been considered to be a pain marker. However, we conclude that in female rats, the abdominal muscle is reflexively activated during physiological urine expulsion. On the other hand, bladder irritation is marked by an exaggeration of this abdominal visceromotor reflex.

Duloxetine for management of stress urinary incontinence

OBJECTIVE

The aim of this article was to review data regarding the efficacy and tolerability of duloxetine, a selective serotonin (5-HT)-norepinephrine (NE) reuptake inhibitor that has received US Food and Drug Administration marketing approval for the treatment of major depressive disorder and painful diabetic neuropathy, and that has been investigated as a treatment for stress urinary incontinence.

METHODS

A MEDLINE/PubMed search was conducted to identify English-language study reports. In addition, proceedings of meetings of the International Continence Society, European Association of Urology, American Urological Association, and American College of Obstetrics and Gynecology were reviewed for relevant abstracts (search terms included duloxetine, thiophenes, serotonin uptake inhibitors, adrenergic uptake inhibitors, and stress urinary incontinence). Additional references were obtained from the bibliographies of these sources. Data for the period from 1986 through January 2005 were reviewed.

RESULTS

All in vitro and in vivo studies of duloxetine were included. Because both 5-HT and NE are involved in the maintenance of urinary continence, duloxetine may have a role in the treatment of urinary incontinence. Duloxetine is primarily eliminated via metabolism, with < 1% of the parent compound excreted via urine. Duloxetine QD or BID has been found to be significantly superior to placebo in reducing incontinence episode frequency (P < 0.001 to P < 0.05), increasing the interval between micturitions (P < 0.001 to P = 0.004), and improving the condition as measured by patient self-report (P < 0.001 to P = 0.028) and incontinence quality-of-life scores (P = 0.002 to P = 0.03). The most problematic adverse events are nausea, dry mouth, constipation, dizziness, and insomnia.

CONCLUSIONS

Although statistically superior to placebo in efficacy trials, the clinical effects of duloxetine therapy on incontinence are small, suggesting that any benefits to the patient would be modest and must be weighed against the drug's adverse event profile. No comparative efficacy/tolerability data with alpha-receptor agonists (eg, pseudoephedrine) are available. On the basis of available data, duloxetine is a modest, but welcome, advance in the pharmacotherapeutic management of stress urinary incontinence.

A randomized crossover study to evaluate Ro 115-1240, a selective alpha1A/1L-adrenoceptor partial agonist in women with stress urinary incontinence

OBJECTIVES

To investigate the potential therapeutic benefits of the selective alpha1A/1l-adrenoceptor partial agonist Ro 115-1240 in women with mild-to-moderate stress urinary incontinence (SUI).

PATIENTS AND METHODS

Thirty-seven women with mild-to-moderate SUI were enrolled in a randomized, placebo-controlled crossover study. Patients received 1.5 mg Ro 115-1240 twice daily or matching placebo for 2 or 4 weeks. Voiding diaries were used to record the number of SUI episodes, urge incontinence episodes and pads used. Sitting blood pressures and heart rate were recorded at each visit.

RESULTS

Ro 115-1240 was associated with a significantly lower mean weekly number of SUI episodes than placebo (8.4 vs 6.0; P= 0.0079), a 28% relative improvement over placebo. There was also a significantly lower mean number of pads used and wet pads changed/week with Ro 115-1240 than with placebo (P = 0.0055 and 0.0066, respectively). The most frequently reported treatment-emergent adverse events were scalp tingling, headache, chills, piloerection, and pruritus. Generally these events were transient and mild to moderate. There was a slightly lower mean sitting heart rate with Ro 115-1240 than with placebo, but no difference in mean systolic or diastolic blood pressure between treatments.

CONCLUSIONS

This study suggests that selective alpha1A/1l-adrenoceptor partial agonists have the potential to improve the symptoms of SUI with little or no cardiovascular effect. These results are encouraging and a randomized controlled trial of Ro 115-1240 in a larger population with SUI is warranted to substantiate these findings.

Duloxetina y otros antidepresivos tricíclicos: efectos farmacodinámicos en el tracto urinario inferior

INTRODUCTION

During years the pharmacology of the lower urinary tract function has been presided by the protagonism of the autonomic nervous system and its components, sympathetic and parasympathetic. Recent investigations proved a greater complexity of micturional dynamics, attributing a more important role to the central nervous system (SNC), to the striated sphincter and to the afferent arc, offering a new opportunity to the Tricyclic Antidepressants (T.A.), reason for this general review.

MATERIAL AND METHODS

Using as reference the work of the First Consultation on Incontinence (Montecarlo, 1999), the previous and later publications about T.A. have been reviewed, including experimental (isometric and "in vivo" studies) and clinical studies, investigating on pharmacological evidences, mechanism of action, tolerance and other effects of T.A.

RESULTS

Only a reduced group of T.A. have been submitted to experimental evaluations and employed in clinical trials. The recent works on Duloxetine have waked up a special interest by their pharmacological potential.

CONCLUSIONS

New knowledge on the peripheral and central control of the continence-miction dynamic offer new pathways for the treatment with T.A., whose effectiveness and tolerance are reviewed.