Intravesical capsaicin as a treatment for refractory detrusor hyperreflexia: a dual center study with long-term followup

Mechanotransduction in the urothelium: ATP signalling and mechanoreceptors

The urothelium, which covers the inner surface of the bladder, is continuously exposed to a complex physical environment where it is stimulated by, and responds to, a wide range of mechanical cues. Mechanically activated ion channels endow the urothelium with functioning in the conversion of mechanical stimuli into biochemical events that influence the surface of the urothelium itself as well as suburothelial tissues, including afferent nerve fibres, interstitial cells of Cajal and detrusor smooth muscle cells, to ensure normal urinary function during the cycle of filling and voiding. However, under prolonged and abnormal loading conditions, the urothelial sensory system can become maladaptive, leading to the development of bladder dysfunction. In this review, we summarize developments in the understanding of urothelial mechanotransduction from two perspectives: first, with regard to the functions of urothelial mechanotransduction, particularly stretch-mediated ATP signalling and the regulation of urothelial surface area; and secondly, with regard to the mechanoreceptors present in the urothelium, primarily transient receptor potential channels and mechanosensitive Piezo channels, and the potential pathophysiological role of these channels in the bladder. A more thorough understanding of urothelial mechanotransduction function may inspire the development of new therapeutic strategies for lower urinary tract diseases.

Acupuncture for Women with Overactive Bladder: Perspective of Traditional Chinese Medicine and Related Mechanism

Purpose

Overactive bladder (OAB) syndrome is one of the most common diseases in urology and affects quality of life. Although the current treatment for OAB is based on oral medications, there are limitations and many patients have difficulty accepting drug-induced adverse effects. This review aimed to analyze the efficacy of acupuncture and its related mechanisms and provide a preliminary therapeutic regimen.

Methods

Two authors independently searched PubMed, Embase, and Cochrane Library up to April 2022. They searched related English literature and extracted the data under a standard form based on the search strategy. Clinical trials which included OAB women with the treatment of acupuncture were included. Common acupuncture alone without other pharmacotherapy, external treatments was in the treatment group. The control interventions may include any active treatments, sham placebo, or no establishment of a control group. Outcomes included 3-day or 24-hour voiding diary, overactive bladder symptom score, etc. The Cochrane risk of bias tool was also used to assess the methodological quality of the randomized controlled trials (RCTs).

Results

We analyzed five RCTs and one comparative study on acupuncture for OAB to review and discuss the acupoint location, treatment course, and retention time based on clinical evidence and treatment ideas in traditional Chinese medicine. Additionally, we used the available evidence to reveal and discuss the acupuncture mechanisms for OAB. Acupuncture may regulate bladder function by inhibiting C-fibers, modulating nerve growth factors and reducing spontaneous contractions of the detrusor muscle.

Conclusion

Combined with the available evidence, the combination of local acupoints and distal acupoints should be necessary to consider, especially the lumbosacral acupoints, the small abdomen acupoints and the lower limb acupoints. Among them, acupuncture at SP4, CV4 and KI3 are strongly recommended. The treatment course of acupuncture should be no less than 4 weeks and maintain the frequency of acupuncture no less than once a week. The duration of each session should be no less than 20 minutes. In addition, investigations remain necessary to verify acupuncture's efficacy and precise mechanism for OAB treatment in further exploration.

Acute Intravesical Capsaicin for the Study of TRPV1 in the Lower Urinary Tract: Clinical Relevance and Potential for Innovation

Capsaicin acts on sensory nerves via vanilloid receptors. TRPV1 has been extensively studied with respect to functional lower urinary tract (LUT) conditions in rodents and humans. We aimed to (1) provide background information on capsaicin and TRPV1 and its mechanisms of action and basis for clinical use, (2) review the use of acute intravesical capsaicin instillation (AICI) in rodents to mimic various LUT disorders in which capsaicin sensitive C-fibers are involved and (3) discuss future innovative treatments. A comprehensive search of the major literature databases until June 2022 was conducted. Both capsaicin-sensitive and resistant unmyelinated bladder afferent C-fibers are involved in non-neurogenic overactive bladder/detrusor overactivity (OAB/DO). AICI is a suitable model to study afferent hyperactivity mimicking human OAB. Capsaicin-sensitive C-fibers are also involved in neurogenic DO (NDO) and potential targets for NDO treatment. AICI has been successfully tested for NDO treatment in humans. Capsaicin-sensitive bladder afferents are targets for NDO treatment. TRPV1-immunoreactive nerve fibers are involved in the pathogenesis of interstitial cystitis/painful bladder syndrome (IC/PBS). The AICI experimental model appears relevant for the preclinical study of treatments targeting bladder afferents for refractory IC/BPS. The activity of capsaicin-sensitive bladder afferents is increased in experimental bladder outlet obstruction (BOO). The AICI model may also be relevant for bladder disorders resulting from C-fiber hyperexcitabilities related to BOO. In conclusion, there is a rationale for the selective blockade of TRPV1 channels for various bladder disorders. The AICI model is clinically relevant for the investigation of pathophysiological conditions in which bladder C-fiber afferents are overexcited and for assessing innovative treatments for bladder disorders based on their pathophysiology.

Role of neurogenic inflammation in local communication in the visceral mucosa

Intense research has focused on the involvement of the nervous system in regard to cellular mechanisms underlying neurogenic inflammation in the pelvic viscera. Evidence supports the neural release of inflammatory factors, trophic factors, and neuropeptides in the initiation of inflammation. However, more recently, non-neuronal cells including epithelia, endothelial, mast cells, and paraneurons are likely important participants in nervous system functions. For example, the urinary bladder urothelial cells are emerging as key elements in the detection and transmission of both physiological and nociceptive stimuli in the lower urinary tract. There is mounting evidence that these cells are involved in sensory mechanisms and can release mediators. Further, localization of afferent nerves next to the urothelium suggests these cells may be targets for transmitters released from bladder nerves and that chemicals released by urothelial cells may alter afferent excitability. Modifications of this type of communication in a number of pathological conditions can result in altered release of epithelial-derived mediators, which can activate local sensory nerves. Taken together, these and other findings highlighted in this review suggest that neurogenic inflammation involves complex anatomical and physiological interactions among a number of cell types in the bladder wall. The specific factors and pathways that mediate inflammatory responses in both acute and chronic conditions are not well understood and need to be further examined. Elucidation of mechanisms impacting on these pathways may provide insights into the pathology of various types of disorders involving the pelvic viscera.

Clinical and Urodynamic Results of Repeated Intradetrusor Onabotulinum Toxin A Injections in Refractory Neurogenic Detrusor Overactivity: Up to 5 Injections in a Cohort of Children With Myelodysplasia

OBJECTIVE

To determine the efficacy and safety of repeated intradetrusor onabotulinum toxin A (onaBoNT-A) injections in children with neurogenic detrusor overactivity due to myelodysplasia.

MATERIALS AND METHODS

The study group consisted of 19 children (4 boys and 15 girls) with a mean age of 10.3 ± 3.1 years old, who had received at least 2 injections of 10 U/kg onaBoNT-A for the treatment of urinary incontinence resistant to anticholinergic treatment and clean intermittent catheterization in our clinic, between 2010 and 2015. Controlled urodynamic studies were performed at the baseline and 3 months after each injection.

RESULTS

Eight of the children received 3 injections, 5 children had 4 injections, and 2 children had 5 injections. From the baseline to the fifth injection, the detrusor compliance (1.3, 4.5, 10, 20.7, 18.8, and 16.6 mL/cm H₂O), the maximum bladder capacity (82.0, 157.0, 191.0, 272.0, 299.0, and 210.5 mL), and the maximum detrusor pressure (55.0, 33.0, 22.0, 12.5, 16.0, and 12.5 cm H₂O) were assessed. The findings significantly improved following the first, second, and third injections, when compared with the previous bladder dynamics (P <.05), but the differences with the fourth were not statistically significant (P >.05). The continence periods were similar under clean intermittent catheterization after all of the injections (P <.05), and no severe side effects were observed.

CONCLUSION

Repeated onaBoNT-A injections are a safe treatment modality and can be offered as an effective alternative choice, instead of more invasive surgery, in children with neurogenic detrusor overactivity due to myelodysplasia.

Intravesical vanilloids for treating neurogenic lower urinary tract dysfunction in patients with multiple sclerosis: A systematic review and meta-analysis. A report from the Neuro-Urology Promotion Committee of the International Continence Society (ICS)

AIMS

To systematically assess all available evidence on efficacy and safety of vanilloids for treating neurogenic lower urinary tract dysfunction (NLUTD) in patients with multiple sclerosis (MS).

METHODS

This systematic review and meta-analysis was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Studies were identified by electronic search of Cochrane register, Embase, Medline, Scopus, (last search January 8, 2016).

RESULTS

After screening of 7848 abstracts, 4 randomized controlled trials (RCTs) and 3 prospective cohort studies were included. Pooled data from three RCTs evaluating intravesical capsaicin showed the standardized mean difference to be -2.16 (95% confidence interval [CI] -2.87 to -1.45) in incontinence episodes per 24 h and -0.54 (95%CI -1.03 to -0.05) in voids per 24 h. There was no statistically significant effect on maximum cystometric capacity and maximum storage detrusor pressure. Overall, adverse events were reported by >50% of the patients, most commonly were pelvic pain, facial flush, worsening of incontinence, autonomic dysreflexia, urinary tract infection and haematuria. Risk of bias and confounding was relevant in both RCTs and non-RCTs.

CONCLUSIONS

Preliminary data suggest that intravesical vanilloids might be effective for treating NLUTD in patients with MS. However, the safety profile seems unfavorable, the overall quality of evidence is low and no licensed substance is currently available warranting well-designed, adequately sampled and properly powered RCTs.

Molecular Surgery Concept from Bench to Bedside: A Focus on TRPV1+ Pain-Sensing Neurons

"Molecular neurosurgery" is emerging as a new medical concept, and is the combination of two partners: (i) a molecular neurosurgery agent, and (ii) the cognate receptor whose activation results in the selective elimination of a specific subset of neurons in which this receptor is endogenously expressed. In general, a molecular surgery agent is a selective and potent ligand, and the target is a specific cell type whose elimination is desired through the molecular surgery procedure. These target cells have the highest innate sensitivity to the molecular surgery agent usually due to the highest receptor density being in their plasma membrane. The interaction between the ligand and its receptor evokes an overactivity of the receptor. If the receptor is a ligand-activated non-selective cation channel, the overactivity of receptor leads to excess Ca²⁺ and Na⁺ influx into the cell and finally cell death. One of the best known examples of such an interaction is the effect of ultrapotent vanilloids on TRPV1-expressing pain-sensing neurons. One intrathecal resiniferatoxin (RTX) dose allows for the receptor-mediated removal of TRPV1+ neurons from the peripheral nervous system. The TRPV1 receptor-mediated ion influx induces necrotic processes, but only in pain-sensing neurons, and usually within an hour. Besides that, target-specific apoptotic processes are also induced. Thus, as a nano-surgery scalpel, RTX removes the neurons responsible for generating pain and inflammation from the peripheral nervous system providing an option in clinical management for the treatment of morphine-insensitive pain conditions. In the future, the molecular surgery concept can also be exploited in cancer research for selectively targeting the specific tumor cell.

Conservative bladder management in advanced multiple sclerosis

Anticholinergics and intermittent catheterization are the cornerstones of bladder management in early multiple sclerosis (MS). In advanced MS however, bladder management is based more on tradition than on evidence. Nurses seem to deal with catheter problems and chronic incontinence. Despite the abundant use of indwelling catheters, there is a lack for guidelines on catheter-induced problems. The psychosexual and social impact of bladder problems in advanced MS is often neglected. The international multidisciplinary special interest group on sexual, urological and bowel dysfunction in MS (SUBDIMS) as a special interest group of the Rehabilitation in Multiple Sclerosis (RIMS) was confronted with a high variability in practice and a lack of guidelines. A literature review was prepared during three multidisciplinary expert meetings. This review will be the basis of further initiatives to improve the urological treatment of patients with advanced MS.

WITHDRAWN: Anticholinergics for urinary symptoms in multiple sclerosis

This review has been withdrawn for the following reasons:

‐ a review author contravenes Cochrane's Commercial Sponsorship Policy. This policy ensures the independence of Cochrane reviews by making sure that there is no bias associated with commercial conflicts of interest in the conduct of Cochrane reviews. The author was employed by the biopharmaceutical company AstraZeneca and cannot say with certainty that the company did not produce or have any financial interest in the interventions in this review

‐ the review is substantially out of date

To view the published versions of this article, please click the 'Other versions' tab.

The editorial group responsible for this previously published document have withdrawn it from publication.

TRP channels in lower urinary tract dysfunction

Lower urinary tract dysfunction (LUTd) represents a major healthcare problem. Although it is mostly not lethal, associated social disturbance, medical costs, loss of productivity and especially diminished quality of life should not be underestimated. Although more than 15% of people suffer from a form of LUTd to some extent, pathophysiology often remains obscure. In the past 20 years, transient receptor potential (TRP) channels have become increasingly important in this field of research. These intriguing ion channels are believed to be the main molecular sensors that generate bladder sensation. Therefore, they are intensely pursued as new drug targets for both curative and symptomatic treatment of different forms of LUTd. TRPV1 was the first of its class to be investigated. Actually, even before this channel was cloned, it had already been targeted in the bladder, with clinical trials of intravesical capsaicin instillations. Several other polymodally gated TRP channels, particularly TRPM8, TRPA1 and TRPV4, also appear to play a prominent role in bladder (patho)physiology. With this review, we provide a brief overview of current knowledge on the role of these TRP channels in LUTd and their potential as molecular targets for treatment.

Influence of urethane-anesthesia on the effect of resiniferatoxin treatment on bladder function in rats with spinal cord injury

AIMS

We investigated the effect of resiniferatoxin (RTX)-treatment on cystometric parameters in the spinal cord injury (SCI) rats in both conscious and urethane-anesthetized conditions and evaluated the influence of urethane-anesthesia on the effect of RTX on lower urinary tract (LUT) function in SCI rats.

METHODS

Female Sprague-Dawley rats were used. SCI was created by transection of the T8-T9 spinal cord. Four weeks after the transection, the animals were placed in a restraint cage for the first cystometric measurements in a conscious state. Secondary cystometric measurements were performed in a conscious condition following the 1 day after RTX-(0.3 mg/kg) or vehicle-subcutaneous injection. Then the animals were injected with urethane (1.5 g/kg, subcutaneously), and cystometric measurements were repeated four times every 1 hr-interval.

RESULTS

After the RTX-treatment in a conscious condition, urinary retention was observed in three out of five animals. In addition, the number of non-voiding contractions (NVCs) significantly decreased although their amplitude did not change significantly. After the urethane-injection, all of the animals treated with RTX developed urinary retention. The amplitude of NVCs significantly decreased, whereas the number of NVCs did not change significantly in the RTX-treated group. No cystometric parameters significantly changed after either vehicle- or urethane-injection in the vehicle-treated group.

CONCLUSIONS

The present results indicate that the suppressive effects of RTX on NVCs as well as voiding contractions in SCI rats can be enhanced by urethane-anesthesia. Such suppressive effect of urethane-anesthesia itself should be taken into consideration when we evaluate a drug-effect on LUT function in rats with SCI.

Cyclophosphamide-induced cystitis reduces ASIC channel but enhances TRPV1 receptor function in rat bladder sensory neurons

Using patch-clamp techniques, we studied the plasticity of acid-sensing ion channels (ASIC) and transient receptor potential V1 (TRPV1) channel function in dorsal root ganglia (DRG) neurons retrogradely labeled from the bladder. Saline (control) or cyclophosphamide (CYP) was given intraperitoneally on days 1, 3, and 5. On day 6, lumbosacral (LS, L6-S2) or thoracolumbar (TL, T13-L2) DRG were removed and dissociated. Bladders and bladder DRG neurons from CYP-treated rats showed signs of inflammation (greater myeloperoxidase activity; lower intramuscular wall pH) and increased size (whole cell capacitance), respectively, compared with controls. Most bladder neurons (>90%) responded to protons and capsaicin. Protons produced multiphasic currents with distinct kinetics, whereas capsaicin always triggered a sustained response. The TRPV1 receptor antagonist A-425619 abolished capsaicin-triggered currents and raised the threshold of heat-activated currents. Prolonged exposure to an acidic environment (pH range: 7.2 to 6.6) inhibited proton-evoked currents, potentiated the capsaicin-evoked current, and reduced the threshold of heat-activated currents in LS and TL bladder neurons. CYP treatment reduced density but not kinetics of all current components triggered by pH 5. In contrast, CYP-treatment was associated with an increased current density in response to capsaicin in LS and TL bladder neurons. Correspondingly, heat triggered current at a significantly lower temperature in bladder neurons from CYP-treated rats compared with controls. These results reveal that cystitis differentially affects TRPV1- and ASIC-mediated currents in both bladder sensory pathways. Acidification of the bladder wall during inflammation may contribute to changes in nociceptive transmission mediated through the TRPV1 receptor, suggesting a role for TRPV1 in hypersensitivity associated with cystitis.

Standard Pharmacological Treatment and New Therapies for Overactive Bladder

The prevalence of overactive bladder (OAB) in adult males varies from 10.2% to 17.4%, and in females from 7.7 to 31.3. 16.5% of the adult population presents symptoms consistent with OAB; of these, 37.2% are actually affected. The OAB has a significant effect on the quality of life. Initial treatment includes behavioral therapy, physiotherapy and antimuscarinic drugs. In patients where behavioral modifications fail, treatment is associated with antimuscarinics. The antimuscarinic agents used to treat OAB showed some efficacy, but adverse events too, such as dry mouth, constipation, headache and blurred vision. In selected cases unresponsive to antimuscarinic therapy, it is possible to use second-line treatments represented by sacral neuromodulation and botulinum toxin type A both for idiopathic detrusor overactivity, where it is still an experimental treatment, and for neurogenic cases with 2011 FDA approval. Surgical options represent the last choice for selected cases.

Percutaneous posterior tibial nerve stimulation as an effective treatment of refractory lower urinary tract symptoms in patients with multiple sclerosis: preliminary data from a multicentre, prospective, open label trial

Background: Percutaneous tibial nerve stimulation (PTNS) has been proposed as a new, minimally invasive neuromodulation technique to treat lower urinary tract symptoms (LUTS).

Objective: To evaluate efficacy, safety and impact on quality of life (QoL) of PTNS on patients with multiple sclerosis (MS) who have LUTS.

Methods: 21 patients (5 men, 16 women) with MS and LUTS unresponsive to anticholinergics were treated with 12 sessions of PTNS. Assessment of LUTS was by validated, self-administered chart and questionnaires, testing the subjective and objective relevance of LUTS for patients and their impact on QoL before and after treatment; the mean post-micturition residual was assessed by trans-abdominal ultrasound scanning. Analysis was by intention to treat.

Results: There was a significant reduction of daytime frequency (from 9 to 6, p = 0.04), nocturia (from 3 to 1, p = 0.002) and mean post-micturition residual (from 98 ± 124 ml to 43 ± 45 ml, p = 0.02). The mean voided volume increased from 182 ± 50 ml to 225 ± 50 ml ( p = 0.003). Eighty-nine percent of patients reported a treatment satisfaction of 70%. Significant improvement in QoL was seen in most domains of the King’s Health QoL questionnaire ( p < 0.05). No adverse events were reported.

Conclusions: PTNS is an effective, safe and well-tolerated treatment for LUTS in patients with MS.

Bladder symptoms in multiple sclerosis: a review of pathophysiology and management

IMPORTANCE OF THE FIELD

The use of anticholinergic medication in bladder dysfunction such as overactive bladder syndrome (OAB) is widespread. However, the benefits and risks of anticholinergics in multiple sclerosis (MS) are unclear because in MS the damage to normal urinary function is both more diffuse and increases with disease progression, and the risk of CNS side effects is higher.

AREAS COVERED IN THIS REVIEW

The pathophysiology of urinary dysfunction in MS and the efficacy and side effects of anticholinergics is assessed. The review analyzed randomized controlled trials and observational studies using anticholinergics involving persons with a confirmed diagnosis of MS having urinary symptoms. Finally a pragmatic approach to managing urinary symptoms in MS is discussed.

WHAT THE READER WILL GAIN

The published data provide limited evidence for the efficacy of anticholinergics in MS. The complexity of treating urinary symptoms in the context of other therapies and the changing neurological background seen in MS is comprehensively analyzed.

TAKE HOME MESSAGE

Anticholinergics could be helpful in particular phases of MS. However, there is inadequate evidence currently available on the use of anticholinergics in MS, and further research on the management of the MS neuropathic bladder is warranted.

Modulation of urinary bladder innervation: TRPV1 and botulinum toxin A

The persisting interest around neurotoxins such as vanilloids and botulinum toxin (BoNT) derives from their marked effect on detrusor overactivity refractory to conventional antimuscarinic treatments. In addition, both are administered by intravesical route. This offers three potential advantages. First, intravesical therapy is an easy way to provide high concentrations of pharmacological agents in the bladder tissue without causing unsuitable levels in other organs. Second, drugs effective on the bladder, but inappropriate for systemic administration, can be safely used as it is the case of vanilloids and BoNT. Third, the effects of one single treatment might be extremely longlasting, contributing to render these therapies highly attractive to patients despite the fact that the reasons to the prolonged effect are still incompletely understood. Attractive as it may be, intravesical pharmacological therapy should still be considered as a second-line treatment in patients refractory to conventional oral antimuscarinic therapy or who do not tolerate its systemic side effects. However, the increasing off-label use of these neurotoxins justifies a reappraisal of their pharmacological properties.

The overactive bladder

Urinary urgency and the associated symptoms which comprise overactive bladder are prevalent amongst the general population and adversely affect quality of life. Disease management consists of a sequential series of options starting with behavioural and lifestyle techniques, pharmacological management (antimuscarinics) and, in severe cases, surgical treatment (urinary diversion, neuromodulation, augmentation cystoplasty and detrusor myectomy). There is increasing recognition of pathophysiological mechanisms in the urothelium, interstitial cells and afferent neurons allowing the importance of peripheral integrative interaction to be identified. The hierarchy of the central nervous system control adds additional complexity to understanding the oflower urinary tract function. Some newer methods of treatment include Botulinum toxin A intramural injections, oral beta-3 adrenergic agonists and rho-kinase inhibitors. The lack of a disease generating hypothesis, the lack of animal models for disease and the subjective nature of the central symptom (urgency) still pose considerable theoretical and scientific hurdles that need to be overcome in the treatment of this condition.

TRPV1: a target for next generation analgesics

Transient Receptor Potential Vanilloid 1 (TRPV1) is a Ca²⁺ permeant non-selective cation channel expressed in a subpopulation of primary afferent neurons. TRPV1 is activated by physical and chemical stimuli. It is critical for the detection of nociceptive and thermal inflammatory pain as revealed by the deletion of the TRPV1 gene. TRPV1 is distributed in the peripheral and central terminals of the sensory neurons and plays a role in initiating action potentials at the nerve terminals and modulating neurotransmitter release at the first sensory synapse, respectively. Distribution of TRPV1 in the nerve terminals innervating blood vessels and in parts of the CNS that are not subjected to temperature range that is required to activate TRPV1 suggests a role beyond a noxious thermal sensor. Presently, TRPV1 is being considered as a target for analgesics through evaluation of different antagonists. Here, we will discuss the distribution and the functions of TRPV1, potential use of its agonists and antagonists as analgesics and highlight the functions that are not related to nociceptive transmission that might lead to adverse effects.

Multiple sclerosis produces significant changes in urinary bladder innervation which are partially reflected in the lower urinary tract functional status-sensory nerve fibers role in detrusor overactivity

BACKGROUND

Detrusor overactivity is often observed in patients with multiple sclerosis (MS), and neurotoxins are emerging as second-line therapies albeit with different degrees of success per patient basis.

OBJECTIVE

To investigate lower urinary tract (LUT) functional status and bladder innervation (calcitonin gene related peptide [CGRP] and substance P [SP] positive nerve fibers) in patients with MS.

METHOD

Eighteen MS patients with LUT symptoms underwent urodynamic investigations, and six non-MS patients undergoing cystoscopy due to microscopic hematuria served as controls. Cold cut bladder biopsies were taken from the bladder trigone region. Neurotransmitter expression was determined by individual immunohistochemical staining.

RESULTS

Two distinct groups could be distinguished: group 1 with pronounced neurogenic detrusor overactivity and mild outflow obstruction; group 2 with some degree of neurogenic detrusor overactivity, detrusor hypocontractility during voiding, and high degree of an outflow obstruction. The presence of SP and CGRP immunoreactive + fiber density was observed in greater numbers in group 1.

CONCLUSION

Density of CGRP and SP positive nerve fibers within the urinary bladder of patients with MS may be suggestive of functional status of the lower urinary tract, namely denser innervation is observed in patients with mild outflow obstruction and strong detrusor overactivity. This observation could be useful when planning second-line treatment (neurotoxins) in these patients. Patients with denser innervation probably will respond better to such a therapy.

Anticholinergics for urinary symptoms in multiple sclerosis

BACKGROUND

Multiple Sclerosis (MS) is the commonest physically disabling chronic neurological disease affecting young people. Urinary symptoms are present in about 68% of people with MS but their basis has a number of potential aetiologies that can change with time.

OBJECTIVES

To assess the absolute and comparative efficacy, tolerability and safety of anticholinergic agents in MS patients.

SEARCH STRATEGY

We searched the Cochrane Multiple Sclerosis Group Specialised Trials Register, the Cochrane Central Register of Controlled Trials (The Cochrane Library 2008, Issue1), MEDLINE (January 1966 to January 2008), EMBASE (January 1974 to January 2008), supplemented with search of reference lists, personal communication with authors and relevant drug manufacturers.

SELECTION CRITERIA

Randomised trials and cross-over trials (blinded and unblinded) that are either placebo-controlled or comparing two or more treatments.

DATA COLLECTION AND ANALYSIS

All four review authors independently assessed eligibility and trial quality, and extracted data. Data were processed as described in the Cochrane Handbook for Systematic Reviews of Interventions.

MAIN RESULTS

Our search strategy identified 33 articles of which thirty were excluded. Three single centre trials were included. No details were given regarding randomisation and blinding in the first two trials but side effects were frequent with all treatments.The first (Hebjorn 1977) was a double blind randomised crossover trial. Thirty four persons with MS received three drugs Methantheline Bromide, Flavoxate Chloride and Meladrazine Tartrate each for 14 days, washout periods were not mentioned. Median volume measurements at the first bladder contraction were statistically significant at a 5% level for Methantheline Bromide only compared to no treatment.The second (Gajewski 1986) was a prospective parallel group randomised study. Thirty four persons with MS were treated for 6-8 weeks with Oxybutynin (19 subjects) or Propantheline (15 subjects). For frequency, nocturia, urgency, and urge incontinence differences in symptom grade in favour of Oxybutynin were found. However, only for frequency the difference was statistically significant at 5% level.The third (Fader 2007) was a double blind crossover trial. Sixty four persons with MS received oral Oxybutynin or intravesical Atropine for 14 days. Details of randomisation and blinding were given. There was no significant difference between the two treatments in any efficacy outcome measure. Side effects and QOL scores showed significant differences in favour of atropine.

AUTHORS' CONCLUSIONS

From the available evidence we cannot advocate the use of anticholinergics in MS.

Emerging drugs for treatment of overactive bladder and detrusor overactivity

BACKGROUND

Overactive bladder (OAB) signifies the presence of urinary urgency and can have major effects on quality of life and social functioning. Standard antimuscarinic drugs have good initial response rates but substantial adverse effects and long-term compliance problems.

OBJECTIVES

To review the complexities of the mechanisms underlying OAB and the current drugs available for treating its symptoms.

METHODS

The literature was reviewed to define current therapies and drugs in clinical trials. Articles were identified by means of a computerised PubMed and Cochrane Library search (using the following keywords: overactive bladder, detrusor overactivity, urgency and bladder), supported by a search of the PharmaProjects database.

CONCLUSIONS

New drug classes, such as beta-3 adrenergic agonists, may work by reducing contractility or excitability of bladder muscle. Moderation of afferent activity may allow improved OAB symptoms, with lower risk of affecting voiding function. Agents acting on the CNS could influence OAB favourably, but target selection and adverse effects are an issue. The recognition of the functional contribution of the urothelium and the diversity of nerve transmitters has sparked interest in both peripheral and central modulation of OAB pathophysiology.

The challenge of overactive bladder therapy: alternative to antimuscarinic agents

Contemporary, the management of overactive bladder (OAB), a medical condition characterized by urgency, with or without urge urinary incontinence, frequency and nocturia, in absence of genitourinary pathologies or metabolic factors that could explain these symptoms, is complex, and a wide range of conservative treatments has been offered, including bladder training, biofeedback, behavioral changes, oral or intravesical anticholinergic agents, S3 sacral neuromodulation and peripheral electrical stimulation. Clinical efficacy of these treatments remains an open issue and several experimental and clinical studies were carried out in the last years improving the results of medical treatment. Here we review the pathophysiology of micturition reflex, the current therapies for OAB and the rationale for alternative treatments. Furthermore we critically address the potential use of medications targeting the central nervous system (CNS) and the primary sensory nerves of the bladder wall, we review the use of agonists of nociceptin/orphanin protein (NOP) receptor and finally we report the results obtained by intradetrusor injection of botulinum toxin.

Intravesical glucidic capsaicin versus glucidic solvent in neurogenic detrusor overactivity: a double blind controlled randomized study

AIMS

Many studies report the use of alcoholic capsaicin instillation to treat neurogenic detrusor overactivity (NDO) in spinal cord injured (SCI) and multiple sclerosis (MS) patients. However, poor tolerability due to the irritative effect of the ethanol solvent limits its use. Our study aimed to evaluate the efficacy and tolerability of a new formulation of capsaicin in a glucidic solution in a multicenter clinical trial.

MATERIALS AND METHODS

Thirty-three patients (26MS/7SCI) suffering from urinary incontinence due to refractory NDO were prospectively enrolled in a double-blind placebo controlled study and randomized to capsaicin group (CG, N = 17) or solvent group (SG, N = 16). They respectively received an intravesical instillation of 100 ml capsaicin diluted in glucidic solvent (CG) or glucidic solvent alone (SG). Efficacy (voiding chart, maximum cystometric capacity (MCC)) and tolerability were evaluated on days 0 (D0), 30 and 90.

RESULTS

On D0, groups were homogeneous. On D30, significant improvement of overactive bladder syndrome and an increase in MCC were shown in CG, whereas there were no improvement in SG. No significant improvement was shown on D90 in both groups. There were no significant differences between groups regarding prevalence, duration, or intensity of side effects, except for short duration pubic pain during instillation more often reported in CG (58.8%) than in SG (12.5%) (P < 0.01).

CONCLUSION

This placebo controlled study using glucidic capsaicin confirms its short-term efficacy in NDO patients. Global tolerance of glucidic capsaicin appeared satisfactory. Long-term efficacy and tolerance of repeated glucidic capsaicin instillations need to be evaluated.

Intravesical resiniferatoxin for the treatment of women with idiopathic detrusor overactivity and urgency incontinence: A single dose, 4 weeks, double-blind, randomized, placebo controlled trial

AIMS

To assess the hypothesis that resiniferatoxin (RTX) can be useful in women with urgency incontinence and idiopathic detrusor overactivity (IDO), we conducted a prospective, double-blind, randomized, placebo-controlled, parallel trial comparing the effects of RTX and placebo.

MATERIALS AND METHODS

Fifty-eight patients were randomly assigned to receive a single intravesical dose of 100 ml of either RTX 50 nM or placebo. Safety and efficacy were evaluated over 4 weeks. The primary efficacy endpoints were voiding symptoms evaluated through the voiding diary. Secondary efficacy endpoint was urodynamic response. Quality of life was measured by the Kings' Health Questionnaire

RESULTS

Although improving trends were seen in both groups after the instillations, no statistically significant differences were found between the groups in any of the clinical or urodynamic parameters. RTX instillations were well tolerated with few and self-limited side-effects.

CONCLUSION

A single 50 nM intravesical dose of RTX was not better than placebo for the treatment of women with IDO and urgency incontinence.

Successful Treatment with Intradetrusor Botulinum-A Toxin for Urethral Urinary Leakage (Catheter Bypassing) in Patients with End-Staged Multiple Sclerosis and Indwelling Suprapubic Catheters

OBJECTIVE

To present the initial results of Botulinum-A toxin (BTA) injection in patients with long-standing multiple sclerosis (MS) and urethral leakage of urine in spite of indwelling suprapubic catheters (catheter bypassing).

METHODS

Study of three patients treated with cystoscopic injection of BTA IU (Allergan). Telephone interviews were made at four- to six-week intervals. Continence status and patient satisfaction were recorded before and after treatment.

RESULTS

Patient 1 remained dry at 48 weeks post injection. Patient 2 became incontinent again after 40 weeks. The third patient was continent when interviewed at 27 weeks following injection, but died two weeks later. The patients were very satisfied with the procedure and there were no complications related to BTA.

CONCLUSIONS

Intradetrusor BTA injection is a very effective and safe treatment for intractable catheter bypassing in patients with neurogenic detrusor overactivity.

Neuromodulatory therapies in female pelvic medicine and reconstructive surgery: biological agents

In recent years, important improvements in the management of patients with neurogenic or non-neurogenic detrusor overactivity and urge incontinence have been brought about by the introduction of vanilloids and botulinum toxins in urology. In this review we introduce the new therapeutic options, provides basic information, and summarize the results experienced so far.

Is sensory urgency part of the same spectrum of bladder dysfunction as detrusor overactivity?

It has been suggested that the urogynecological diagnosis of sensory urgency is an early form of detrusor overactivity and may be just earlier in the spectrum of disease. The former term is generally defined as increased perceived bladder sensation during filling, a low first desire to void and low bladder capacity in the absence of recorded urinary tract infection (UTI) or detrusor overactivity. The aims of this study are to determine the prevalence and associations of sensory urgency in comparison with detrusor overactivity, and whether sensory urgency is shown to be in the same spectrum of bladder dysfunction as detrusor overactivity. Five hundred and ninety-two women attending for an initial urogynecological/urodynamic assessment took part in this prospective study. In addition to a full clinical assessment, all women underwent free uroflowmetry, residual urine volume measurement (by vaginal ultrasound) and multichannel filling and voiding cystometry. Data were separated into those having (1) sensory urgency or (2) detrusor overactivity. Apart from prevalence figures, comparative associations were sought for (3) age; (4) parity; (5) presenting symptoms; (6) presence of at least one (medically) documented UTI in the previous 12 months; (7) two or more (recurrent) documented UTIs in the previous 12 months; (8) prior hysterectomy; (9) prior continence surgery; (10) menopause; (11) menopause and HRT use; (12) sign of clinical stress leakage; (13) retroverted uterus; (14) anterior vaginal wall prolapse; (15) uterine prolapse; (16) posterior vaginal wall prolapse; (17) apical vaginal prolapse; (18, 19) maximum, average urine flow rate (MUFR, AUFR) centiles, Liverpool Nomograms; (20) median residual urine volume (RUV) in milliliters; (21, 22) voiding difficulty: VD1,VD2 (MUFR, AUFR under 10th centile Liverpool Nomogram and/or RUV >30 ml); (23) diagnosis of urodynamic stress incontinence and (24) diagnosis of uterine and/or vaginal prolapse (grade >0). The prevalence of sensory urgency was 13%. The only differences in the clinical and urodynamic profiles of it and detrusor overactivity were (1) significantly increased prevalence of the symptom of urge incontinence and (2) (by definition) abnormal detrusor contractions during filling cystometry in women with detrusor overactivity. Overall, sensory urgency and detrusor overactivity appear to be part of the same spectrum of bladder dysfunction.

TRPV1 (vanilloid receptor) in the urinary tract: expression, function and clinical applications

The transient receptor potential vanilloid subfamily 1 (TRPV1) is an ion channel activated by capsaicin, heat, protons and endogenous ligands such as anandamide. It is largely expressed in the urinary tract of mammals. Structures in which the receptor expression is firmly established include sensory fibers and urothelial cells, although the presence of TRPV1 in other cell types has been reported. As in other systems, pain perception was the first role attributed to TRPV1 in the urinary tract. However, it is now increasingly clear that TRPV1 also regulates the frequency of bladder reflex contractions, either through direct excitation of sensory fibers or through urothelial-sensory fiber cross talk involving the release of neuromediators from the epithelial cells. In addition, the recent identification of the receptor in urothelial and prostatic cancer cells raise the exciting hypothesis that TRPV1 is involved in cell differentiation. Desensitization of the receptor by capsaicin and resiniferatoxin has been investigated for therapeutic purposes. For the moment, lower urinary tract dysfunctions in which some benefit was obtained include painful bladder syndrome and overactive bladder of neurogenic and non-neurogenic origin. However, desensitization may become obsolete when non-toxic, potent TRPV1 antagonists become available.

Improving the global management of the neurogenic bladder patient: part II. Future treatment strategies

BACKGROUND

Patients with neurogenic bladder represent a small fraction of the total overactive bladder population. As a consequence, development of new therapies in this area has largely focused on idiopathic urinary incontinence. The absence of data for patients with neurological disease has far-reaching implications, affecting reimbursement and physicians' willingness to prescribe therapies, and limiting access of potential valuable treatments to patients whose lives are significantly impaired by inadequately managed bladder symptoms.

SCOPE

The range of new therapies is increasing. Although many reviews of the overall safety, efficacy and mode of action of such treatments are available, there is limited information on how these treatments will best be used in clinical practice. We considered the current benefits and limitations of the various new licensed and unlicensed therapies and what role each would have in the future management of neurogenic urinary incontinence.

CONCLUSIONS

A wide range of new treatments have been investigated for the management of overactive bladder; few, however, have been evaluated extensively in neurogenic urinary incontinence. Further studies are required to determine the optimal dosing regimes and formulations for individual sub-populations of neurogenic bladder patients and to determine the cost-effectiveness of these interventions. With the current experience available, two treatment algorithms for a subset of patients with neurological disease have also been proposed, which suggest at which stage of management and in which patients individual therapies for neurogenic urinary incontinence could be used.

Intravesical Therapy for Overactive Bladder

Overactive bladder and urgency incontinence are common conditions generally treated with oral anticholinergic therapy. Despite the development of new antimuscarinic agents, many patients do not tolerate or fail to respond to oral therapy. Intravesical instillation therapy can provide an alternative method of managing bladder overactivity. Intravesical instillation of anticholinergics such as oxybutynin and atropine can achieve cholinergic blockade without producing systemic side effects. Botulinum A toxin injected directly into the detrusor has been shown in preliminary studies to increase bladder capacity and decrease uncontrolled bladder contractility for up to 6 months. Intravesical local anesthetics such as lidocaine and bupivacaine block the conduction of unmyelinated C fibers and when administered into the bladder, lead to an increase in functional bladder capacity. Intravesical capsaicin and resiniferatoxin also affect afferent innervation by blocking C-fiber afferents, leading to decreased bladder contractility and increased bladder capacity. Intravesical instillation therapy can provide an alternative treatment for the management of overactive bladder.

Botulinum Toxin Type A Injections for Treating Neurogenic Detrusor Overactivity Combined With Low-Compliance Bladder in Patients With Spinal Cord Lesions

OBJECTIVE

To evaluate botulinum toxin type A (BTX-A) for treating neurogenic detrusor overactivity in patients with spinal cord lesions, including those with abnormally low bladder compliance.

DESIGN

Nonrandomized, before-after trial (9-mo follow-up).

SETTING

Hospitalized care.

PARTICIPANTS

Ten patients with high detrusor contraction pressure and/or poor response to oxyphencyclimine with incontinence selected as a consecutive sample.

INTERVENTION

BTX-A (Botox; 300U) was injected into the detrusor muscle.

MAIN OUTCOME MEASURES

Urinary continence, functional bladder capacity, bladder compliance, detrusor contraction pressure, and volume at first reflex voiding. Measurements were taken before and 6, 16, and 36 weeks posttreatment.

RESULTS

Six weeks after treatment, complete continence was restored in 7 patients without oxyphencyclimine. Mean functional bladder capacity (P=.008), compliance (P=.012), and reflex volume (P=.045) significantly increased, whereas maximal detrusor contraction pressure significantly decreased (P<.001). Urodynamic variables remained significantly improved at 16 weeks, but values were returning toward baseline levels by 36 weeks. The procedure was generally uneventful, without any serious side effects.

CONCLUSIONS

BTX-A injections are an effective, well-tolerated treatment for neurogenic detrusor overactivity in patients with spinal cord lesions, even in patients with abnormally low bladder compliance. Patients may require repeat injections after 16 weeks to remain continent.

Newer pharmacologic options in management of overactive bladder syndrome

PURPOSE OF REVIEW

Urinary incontinence is an under-reported epidemic that currently affects an estimated 13 million people in the United States, of whom about 11 million are women, according to the National Institute of Diabetes and Digestive and Kidney Diseases (Publication No. 02-4132). Because many patients are unaware of curative options and perceive it to be an inevitable outcome of advancing age, they fail to report their symptoms and increase their risk of developing associated co-morbid disease. Failure to diagnose and treat this condition increases financial burdens on individuals, their families and health care organizations.

RECENT FINDINGS

Pharmacologic therapy of urge incontinence previously had limited treatment success because efficacious drugs were poorly tolerated, resulting in low patient compliance. Tolerance and effectiveness continue to be improved due to innovative new drugs and alternative delivery systems.

SUMMARY

The goal of this review is to update the clinician on the efficacy and the tolerability of established and investigational pharmacologic modalities of therapy.

Transplants of fibroblasts expressing BDNF and NT-3 promote recovery of bladder and hindlimb function following spinal contusion injury in rats

We examined whether fibroblasts, genetically modified to express BDNF and NT-3 (Fb-BDNF/NT3) and transplanted into a thoracic spinal injury site, would enhance recovery of bladder function and whether this treatment would be associated with reorganization of lumbosacral spinal circuits implicated in bladder function. Rats received modified-moderate contusion injuries at T8/9, and 9 days later, Fb-BDNF/NT3 or unmodified fibroblasts (OP-controls) were delivered into the cord. Fb-BDNF/NT3 rats recovered from areflexic bladder earlier, showed decreased micturition pressure and fewer episodes of detrusor hyperreflexia, compared to OP-controls. There were also improvements in hindlimb function in the Fb-BDNF/NT3 group although locomotion on a more challenging substrate (grid) and tail withdrawal latency in response to a thermal stimulus showed persisting deficits, little recovery, and no differences between the groups. Immunocytochemistry at L6-S1 revealed changes in density of afferent and descending projections to L6-S1 cord. The density of small dorsal root axons increased in the superficial layers of the dorsal horn in OP-controls but not in Fb-BDNF/NT3, suggesting sprouting of primary afferents following injury that was inhibited by Fb-BDNF/NT-3. In contrast, the trophic factor secreting transplants stimulated sprouting and/or sparing of descending modulatory pathways projecting to the lumbosacral spinal cord. No differences in synaptophysin immunoreactivity were seen in the dorsal horn which suggested that synaptic density was similar but achieved by sprouting of different systems in the two operated groups. Fb-BDNF/NT3 transplanted into injured spinal cord thus improved both bladder and hindlimb function, and this was associated with reorganization of spinal circuitry.

Urinary urge incontinence: causes and management strategies

Bladder control is a skill most people learn in childhood, so if control is lost in adult life the impact can be very significant, particularly on the quality of life of the person affected. There are many causes of loss of bladder control, ranging from neurological conditions to menopause, as well as certain medications. This article discusses urinary urgency and urge incontinence, examines its causes and diagnosis, and provides an overview of the nursing interventions available to treat the problem.

The role of the vanilloid (capsaicin) receptor (TRPV1) in physiology and pathology

The cloning of the vanilloid receptor 1 opened a floodgate for discoveries regarding the function of this complex molecule. It has been found that, in addition to heat, protons and vanilloids, this receptor also responds to various endogenous ligands. Furthermore, it has been also emerged that, through associations with other molecules, the vanilloid receptor 1 plays an important role in the integration of various stimuli and modulation of cellular excitability. Although, originally, the vanilloid receptor 1 was associated with nociceptive primary afferent fibres, it has been gradually revealed that it is broadly expressed in the brain, epidermis and visceral cells. The expression pattern of the vanilloid receptor 1 indicates that it could be involved in various physiological functions and in the pathomechanisms of diverse diseases. Here, we summarise the molecular, pharmacological and physiological characteristics, and putative functions, of the vanilloid receptor 1, and discuss the therapeutic potential of this molecule.

Success of repeat detrusor injections of botulinum a toxin in patients with severe neurogenic detrusor overactivity and incontinence

OBJECTIVES

Detrusor injections with botulinum toxin type A are an effective treatment for neurogenic detrusor overactivity, lasting for 9-12 months. When the patients develop botulinum resistance, subsequent injections might be less effective. Repeat injections in patients with severe neurogenic detrusor overactivity and incontinence were studied.

METHODS

Patients received Botox (300 UI) or Dysport (750 UI) injections. Clinical variables: satisfaction, anticholinergics use, mean and maximum bladder capacity, continence volume. Cystometric parameters: compliance, cystometric capacity, reflex volume.

STATISTICS

Anova, chi2-tests; t-tests and paired t-tests (p=0.05).

RESULTS

Forty-three men and 23 women (mean age 38.3 years; mean duration of lesion 9.2 years) were included. The interval between subsequent injections (on average 9-11 months) did not change significantly (p=0.5594). The satisfaction was high and anticholinergics use decreased substantially (p=0.0000). Significant improvements were found in clinical parameters and in cystometric capacity, for compliance only at the second treatment. The incidence of reflex contractions was significantly reduced. Four patients had transient adverse events after Dysport.

CONCLUSIONS

Repeat injections with botulinum toxin type A are as effective as the first one. The cause for repeat treatment is relapse of overactive bladder symptoms.

Capsaicin-induced apoptosis and reduced release of reactive oxygen species in MBT-2 Murine Bladder Tumor cells

Bladder cancer is a common cancer with high risk of recurrence and mortality. Intravesicle chemotherapy after trans-urethral resection is required to prevent tumor recurrence and progression. It has been known that antioxidants enhance the antitumor effect of bacillus Calmette-Guerin (BCG), the most effective intravesical bladder cancer treatment. Capsaicin, the major pungent ingredient in genus Capsicum, has recently been tried as an intravesical drug for overactive bladder and it has also been shown to induce apoptotic cell death in many cancer cells. In this study, we investigated the apoptosis-inducing effect and alterations in the cellular redox state of capsaicin in MBT-2 murine bladder tumor cells. Capsaicin induced apoptotic MBT-2 cell death in a time- and dose-dependent manner. The capsaicin-induced apoptosis was blocked by the pretreatment with Z-VAD-fmk, a broad-range caspase inhibitor, or Ac-DEVD-CHO, a caspase-3 inhibitor. In addition to the caspase-3 activation, capsaicin also induced cytochrome c release and decrease in Bcl-2 protein expression with no changes in the level of Bax. Furthermore, capsaicin at the concentration of inducing apoptosis also markedly reduced the level of reactive oxygen species and lipid peroxidation, implying that capsaicin may enhance the antitumor effect of BCG in bladder cancer treatment. These results further suggest that capsaicin may be a valuable intravesical chemotherapeutic agent for bladder cancers.

Management of secondary-progressive multiple sclerosis

The majority of patients with relapse-onset multiple sclerosis (MS) will go on to develop secondary-progressive MS (SPMS) disease, with approximately 50% developing SPMS after 10 years. It remains unknown whether the relapsing and progressive phases of MS differ qualitatively. The pathogenesis of SPMS is poorly understood. The specific role that inflammation plays in disease progression is not well defined. Immunosuppressive therapies, which are capable of reducing or stopping clinical relapses and suppressing MRI activity, generally do not stop disease progression. Recent natural history studies suggest that disease progression occurs regardless of the presence of superimposed relapses. However, poor recovery from clinical relapses does account for the acquisition of disability. Therefore, stopping relapses with appropriate therapy delays the acquisition of disability but does not necessarily delay or prevent the development of SPMS. At present, the only disease-modifying therapies licensed for use in SPMS are interferon-beta-1b in Europe and the US, and mitoxantrone in the US. These agents can only be recommended for patients who continue to have relapses. Symptomatic therapies remain the cornerstone of treatment for patients with SPMS. Delivering high-quality, effective symptomatic therapies requires a multidisciplinary approach. The aim of symptomatic therapies should not only be to reduce neurological impairments but also to decrease disability and handicap and to improve the emotional well-being and health-related quality of life of patients with SPMS.

Cool (TRPM8) and hot (TRPV1) receptors in the bladder and male genital tract

PURPOSE

Overactive bladder symptoms due to various etiologies have been successfully treated with capsaicin by desensitization of the temperature sensitive vanilloid receptor TRPV1. Recently another temperature sensitive receptor, TRPM8, activated by menthol and cool temperatures (8C to 28C) was described that may be the proposed cool receptor, at least in part mediating the bladder response in the diagnostic ice water test. We defined the sites of mRNA and protein expression of TRPM8 and TRPV1 in the rat and human genitourinary tract.

MATERIALS AND METHODS

Prostate, testis, penis, bladder and dorsal root ganglion tissue was obtained from rats. Prostate, testicle, seminiferous tubules, corpus cavernosum, glans, overlying glans skin, scrotal skin and bladder were obtained from human patients. Reverse transcription-polymerase chain reaction was done using species specific primers for TRPM8 and TRPV1. Immunofluorescence staining for TRPM8 was performed in rat tissues as well as in cultured human urothelial cells.

RESULTS

TRPM8 and TRPV1 mRNA were detected in all rat tissues. Human samples demonstrated TRPM8 mRNA in prostate, testicle, seminiferous tubules, scrotal skin and bladder. No TRPM8 mRNA was identified in human corpus cavernosum, glans or overlying glans skin. Separation of layers in human bladder demonstrated mRNA for TRPM8 only in the urothelium and not in the detrusor. Immunofluorescence location of TRPM8 was found in rat prostate, DRG and bladder, and in human urothelial cells in culture. TRPV1 mRNA was detected in all human genitourinary tract tissues.

CONCLUSIONS

These results demonstrate that mRNA and protein for TRPM8 exist in multiple genitourinary organs in the rat and human, and it may be considered a possible new target, as is TRPV1, for the pharmacological treatment of detrusor overactivity or other urological disorders.

Physiology of incontinence

The physiology of incontinence is related to the normal physiologic mechanisms of aging and to abnormal pathologic changes that recently have become better understood. Further research is needed to develop new methods of pharmacologic treatment.

Pharmacologic management of urinary incontinence

Urinary incontinence is a highly prevalent and difficult to treat medical condition. For those who are affected, urinary incontinence produces profound modifications in lifestyle and perceived quality of life. Pharmacologic therapy clearly is beneficial for most types of urinary incontinence. The low therapeutic success of current treatments and obnoxious side effects, however, limit patient satisfaction and compliance. There is a considerable need for improved therapeutic options to treat this devastating condition.