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Grundy L, Wyndaele JJ, Hashitani H, Vahabi B, Wein A, Abrams P, Chakrabarty B, Fry CH. How does the lower urinary tract contribute to bladder sensation? ICI-RS 2023. Neurourol Urodyn 2024; 43:1293-1302. [PMID: 37902296 DOI: 10.1002/nau.25316] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2023] [Accepted: 10/17/2023] [Indexed: 10/31/2023]
Abstract
AIM Bladder sensation is critical for coordinating voluntary micturition to maintain healthy bladder function. Sensations are initiated by the activation of sensory afferents that innervate throughout the bladder wall. However, the physiological complexity that underlies the initiation of bladder sensory signaling in health and disease remains poorly understood. This review summarises the latest knowledge of the mechanisms underlying the generation of bladder sensation and identifies key areas for future research. METHODS Experts in bladder sensory signaling reviewed the literature on how the lower urinary tract contributes to bladder sensation and identified key research areas for discussion at the 10th International Consultation on Incontinence-Research Society. RESULTS The importance of bladder sensory signals in maintaining healthy bladder function is well established. However, better therapeutic management of bladder disorders with exaggerated bladder sensation, including overactive bladder syndrome (OAB) and interstitial cystitis/bladder pain syndrome (IC/BPS) is limited by a lack of knowledge in a number of key research areas including; the contribution of different nerves (pudendal, pelvic, hypogastric) to filling sensations in health and disease; the relative contribution of stretch sensitive (muscular) and stretch-insensitive (mucosal) afferents to bladder sensation in health and disease; the direct and indirect contributions of the muscularis mucosae to bladder contraction and sensation; and the impact of manipulating urothelial release factors on bladder sensation. CONCLUSION Disturbances in bladder sensory signaling can have severe consequences for bladder sensation and function including the development of OAB and IC/BPS. Advancing therapeutic treatments for OAB and IC/BPS requires a deeper understanding of the mechanisms underlying the generation of bladder sensation, and key areas for future research have been identified.
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Affiliation(s)
- Luke Grundy
- Neurourology Research Group, Flinders Health and Medical Research Institute, Flinders University, South Australia, Australia
| | | | - Hikaru Hashitani
- Department of Cell Physiology, Nagoya City University, Nagoya, Japan
| | - Bahareh Vahabi
- School of Applied Sciences, University of the West of England, Bristol, UK
| | - Alan Wein
- Perelman School of Medicine, Penn Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Desai Sethi Institute of Urology, Miller School of Medicine, University of Miami, Miami, Florida, USA
| | - Paul Abrams
- Bristol Urological Institute, Southmead Hospital Bristol, Bristol, UK
| | - Basu Chakrabarty
- School of Physiology, Pharmacology & Neuroscience, University of Bristol, Bristol, UK
| | - Christopher H Fry
- School of Physiology, Pharmacology & Neuroscience, University of Bristol, Bristol, UK
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2
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Kwon J, Kim DY, Cho KJ, Hashimoto M, Matsuoka K, Kamijo T, Wang Z, Karnup S, Robertson AM, Tyagi P, Yoshimura N. Pathophysiology of Overactive Bladder and Pharmacologic Treatments Including β3-Adrenoceptor Agonists -Basic Research Perspectives. Int Neurourol J 2024; 28:12-33. [PMID: 38461853 DOI: 10.5213/inj.2448002.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2023] [Accepted: 01/10/2024] [Indexed: 03/12/2024] Open
Abstract
Overactive bladder (OAB) is a symptom-based syndrome defined by urinary urgency, frequency, and nocturia with or without urge incontinence. The causative pathology is diverse; including bladder outlet obstruction (BOO), bladder ischemia, aging, metabolic syndrome, psychological stress, affective disorder, urinary microbiome, localized and systemic inflammatory responses, etc. Several hypotheses have been suggested as mechanisms of OAB generation; among them, neurogenic, myogenic, and urothelial mechanisms are well-known hypotheses. Also, a series of local signals called autonomous myogenic contraction, micromotion, or afferent noises, which can occur during bladder filling, may be induced by the leak of acetylcholine (ACh) or urothelial release of adenosine triphosphate (ATP). They can be transmitted to the central nervous system through afferent fibers to trigger coordinated urgency-related detrusor contractions. Antimuscarinics, commonly known to induce smooth muscle relaxation by competitive blockage of muscarinic receptors in the parasympathetic postganglionic nerve, have a minimal effect on detrusor contraction within therapeutic doses. In fact, they have a predominant role in preventing signals in the afferent nerve transmission process. β3-adrenergic receptor (AR) agonists inhibit afferent signals by predominant inhibition of mechanosensitive Aδ-fibers in the normal bladder. However, in pathologic conditions such as spinal cord injury, it seems to inhibit capsaicin-sensitive C-fibers. Particularly, mirabegron, a β3-agonist, prevents ACh release in the BOO-induced detrusor overactivity model by parasympathetic prejunctional mechanisms. A recent study also revealed that vibegron may have 2 mechanisms of action: inhibition of ACh from cholinergic efferent nerves in the detrusor and afferent inhibition via urothelial β3-AR.
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Affiliation(s)
- Joonbeom Kwon
- Department of Urology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
- Leaders Urology Clinic, Daegu, Korea
| | - Duk Yoon Kim
- Department of Urology, Catholic University of Daegu School of Medicine, Daegu, Korea
| | - Kang Jun Cho
- Department of Urology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
- Department of Urology, College of Medicine, The Catholic University of Korea, Seoul, Korea
| | - Mamoru Hashimoto
- Department of Urology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Kanako Matsuoka
- Department of Urology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Tadanobu Kamijo
- Department of Urology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Zhou Wang
- Department of Urology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Sergei Karnup
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Anne M Robertson
- Department of Mechanical Engineering and Materials Science, University of Pittsburgh School of Bioengineering, Pittsburgh, PA, USA
| | - Pradeep Tyagi
- Department of Urology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Naoki Yoshimura
- Department of Urology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
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Phelps C, Chess-Williams R, Moro C. The role of intracellular calcium and Rho kinase pathways in G protein-coupled receptor-mediated contractions of urinary bladder urothelium and lamina propria. Am J Physiol Cell Physiol 2023; 324:C787-C797. [PMID: 36689673 PMCID: PMC10027080 DOI: 10.1152/ajpcell.00441.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The influence of extracellular and intracellular calcium on smooth muscle contractile activity varies between organs. In response to G protein-coupled receptor (GPCR) stimulation, the urinary bladder detrusor muscle has shown a 70% dependence on extracellular calcium, whereas the urothelium and lamina propria (U&LP) has a 20%-50% dependence. However, as this only accounts for partial contractile activity, the contribution of intracellular calcium and calcium sensitization pathways remains unclear. This study assessed the role of intracellular signaling pathways on GPCR-mediated urinary bladder U&LP contraction. Porcine U&LP responses to activation of the Gq/11-coupled muscarinic, histamine, 5-hydroxytryptamine (serotonin), neurokinin, prostaglandin, and angiotensin II receptors were assessed with three selective inhibitors of store-released intracellular calcium, 2-aminoethyl diphenylborinate (2-APB), cyclopiazonic acid (CPA), and ruthenium red, and three Rho kinase inhibitors, fasudil, Y-27632, and GSK269962. There was no discernible impact on receptor agonist-induced contractions of the U&LP after blocking intracellular calcium pathways, suggesting that this tissue is more sensitive to alterations in the availability of extracellular calcium. However, an alternative mechanism of action for GPCR-mediated contraction was identified to be the activation of Rho kinase, such as when Y-27632 significantly reduced the GPCR-mediated contractile activity of the U&LP by approximately 50% (P < 0.05, n = 8). This suggests that contractile responses of the bladder U&LP do not involve a significant release of calcium from intracellular stores, but that Gq/11-coupled receptor activation causes calcium sensitization via Rho kinase. This study highlights a key role for Rho kinase in the urinary bladder, which may provide a novel target in the future pharmaceutical management of bladder contractile disorders.
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Affiliation(s)
- Charlotte Phelps
- Centre for Urology Research, Faculty of Health Sciences and Medicine, Bond University, Gold Coast, Queensland, Australia
| | - Russ Chess-Williams
- Centre for Urology Research, Faculty of Health Sciences and Medicine, Bond University, Gold Coast, Queensland, Australia
| | - Christian Moro
- Centre for Urology Research, Faculty of Health Sciences and Medicine, Bond University, Gold Coast, Queensland, Australia
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Phelps C, Chess-Williams R, Moro C. The Dependence of Urinary Bladder Responses on Extracellular Calcium Varies Between Muscarinic, Histamine, 5-HT (Serotonin), Neurokinin, Prostaglandin, and Angiotensin Receptor Activation. Front Physiol 2022; 13:841181. [PMID: 35431993 PMCID: PMC9008219 DOI: 10.3389/fphys.2022.841181] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Accepted: 03/14/2022] [Indexed: 12/20/2022] Open
Abstract
With many common bladder diseases arising due to abnormal contractions, a greater understanding of the receptor systems involved may aid the development of future treatments. The aim of this study was to identify any difference in the involvement of extracellular calcium (Ca2+) across prominent contractile-mediating receptors within cells lining the bladder. Strips of porcine urothelium and lamina propria were isolated from the urinary bladder dome and mounted in isolated tissue baths containing Krebs-bicarbonate solution, perfused with carbogen gas at 37°C. Tissue contractions, as well as changes to the frequency and amplitude of spontaneous activity were recorded after the addition of muscarinic, histamine, 5-hydroxytryptamine, neurokinin-A, prostaglandin E2, and angiotensin II receptor agonists in the absence and presence of 1 µM nifedipine or nominally zero Ca2+ solution. The absence of extracellular Ca2+ influx after immersion into nominally zero Ca2+ solution, or the addition of nifedipine, significantly inhibited the contractile responses (p < 0.05 for all) after stimulation with carbachol (1 µM), histamine (100 µM), 5-hydroxytryptamine (100 µM), neurokinin-A (300 nM), prostaglandin E2 (10 µM), and angiotensin II (100 nM). On average, Ca2+ influx from extracellular sources was responsible for between 20–50% of receptor-mediated contractions. This suggests that although the specific requirement of Ca2+ on contractile responses varies depending on the receptor, extracellular Ca2+ plays a key role in mediating G protein-coupled receptor contractions of the urothelium and lamina propria.
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Takeya M, Higashi R, Hashitani H, Nakamura KI, Hayashi T, Nakashima N, Takano M. PDGFRα (+) subepithelial interstitial cells act as a pacemaker to drive smooth muscle of the guinea pig seminal vesicle. J Physiol 2022; 600:1703-1730. [PMID: 35081665 DOI: 10.1113/jp281686] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Accepted: 01/18/2022] [Indexed: 11/08/2022] Open
Abstract
KEY POINTS In many visceral smooth muscle organs, spontaneous contractions are electrically driven by non-muscular pacemaker cells. In guinea pig seminal vesicles (SVs), as yet unidentified mucosal cells appear to drive neighbouring smooth muscle cells (SMCs). Two populations of spontaneously active cells are distributed in the SV mucosa. Basal epithelial cells (BECs) generate asynchronous, irregular spontaneous Ca2+ transients and spontaneous transient depolarisations (STDs). In contrast, subepithelial interstitial cells (SICs) develop synchronous Ca2+ oscillations and electrical slow waves. Pancytokeratin-immunoreactive (IR) BECs are located on the apical side of the basement membrane (BM), while platelet-derived growth factor receptor α (PDGFRα)-IR SICs are located on the basal side of the BM. Spontaneous Ca2+ transients in SICs are synchronised with those in SV SMCs. Dye-coupling between SICs and SMCs suggests that SICs act as pacemaker cells to drive the spontaneous contractions of SV smooth muscle. ABSTRACT Smooth muscle cells (SMCs) of the guinea pig seminal vesicle (SV) develop spontaneous phasic contractions, Ca2+ flashes and electrical slow waves in a mucosa dependent manner, thus it was envisaged that pacemaker cells reside in the mucosa. Here, we aimed to identify the pacemaker cells in SV mucosa using intracellular microelectrode and fluorescent Ca2+ imaging techniques. Morphological characteristics of the mucosal pacemaker cells were also investigated using focused ion beam/scanning electron microscopy tomography and fluorescent immunohistochemistry. Two populations of mucosal cells developed spontaneous Ca2+ transients and electrical activity, namely basal epithelial cells (BECs) and subepithelial interstitial cells (SICs). Pancytokeratin-immunoreactive BECs were located on the apical side of the basement membrane (BM) and generated asynchronous, irregular spontaneous Ca2+ transients and spontaneous transient depolarisations (STDs). The spontaneous Ca2+ transients and STDs were not diminished by 10 μM nifedipine but abolished by 10 μM cyclopiazonic acid (CPA). Platelet-derived growth factor receptor α (PDGFRα)-immunoreactive SICs were distributed just beneath the basal side of the BM and developed synchronous Ca2+ oscillations (SCOs) and electrical slow waves, which were suppressed by 3 μM nifedipine and abolished by 10 μM CPA. In SV mucosal preparations in which some smooth muscle bundles remained attached, SICs and residual SMCs developed temporally-correlated spontaneous Ca2+ transients. Neurobiotin injected into SICs spread to not only neighbouring SICs but also to neighbouring SMCs or vice versa. These results suggest that PDGFRα (+) SICs electrotonically drive the spontaneous contractions of SV smooth muscle. Abstract figure legend The seminal vesicles (SVs) of guinea pig generate spontaneous phasic contractions (SPCs). SV smooth muscle cells (SMCs, pink) develop SPCs associated with spontaneous electrical slow waves and Ca2+ flashes, which require the attachment of mucosal layer. Histological examination demonstrated the layer of PDGFRα-immunoreactive subepithelial interstitial cells (SICs, green) underneath of the basement membrane. The SICs spontaneously develop synchronous Ca2+ oscillations and the electrical slow waves, at the frequency corresponding to those of SPCs. The dye-coupling between SICs and SMCs further suggested that the synchronous electrical slow waves in the SICs electrotonically conduct to the SV SMCs via gap junctions (orange). Thus, the SICs appear to act as electrical pacemaker cells driving SPCs of SV. The basal epithelial cells (BECs, brown) also generated asynchronous, irregular spontaneous Ca2+ transients and spontaneous transient depolarisations, although their roles in developing SPCs remains to be explored. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Mitsue Takeya
- Division of Integrated Autonomic Function, Department of Physiology, Kurume University School of Medicine, Kurume, Japan
| | - Ryuhei Higashi
- Electron Microscopic Laboratory, Central Research Unit of Kurume University School of Medicine, Kurume, Japan
| | - Hikaru Hashitani
- Department of Cell Physiology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Kei-Ichiro Nakamura
- Division of Microscopic and Developmental Anatomy, Department of Anatomy, Kurume University School of Medicine, Kurume, Japan
| | | | - Noriyuki Nakashima
- Division of Integrated Autonomic Function, Department of Physiology, Kurume University School of Medicine, Kurume, Japan
| | - Makoto Takano
- Division of Integrated Autonomic Function, Department of Physiology, Kurume University School of Medicine, Kurume, Japan
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Rac1 silencing, NSC23766 and EHT1864 reduce growth and actin organization of bladder smooth muscle cells. Life Sci 2020; 261:118468. [PMID: 32961232 DOI: 10.1016/j.lfs.2020.118468] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Revised: 09/07/2020] [Accepted: 09/15/2020] [Indexed: 12/16/2022]
Abstract
AIMS RacGTPase-mediated proliferation and smooth muscle contraction in the lower urinary tract has been recently suggested and may offer putative targets for treamtment of lower urinary tract symptoms. However, RacGTPase function for proliferation of detrusor smooth muscle cells is unknown and the specificity of Rac inhibitors has been questioned. Here, we examined effects of Rac1 knockdown and of the Rac inhibitors NSC23766 and EHT1864 in human bladder smooth muscle cells (hBSMCs). MAIN METHODS Rac1 expression was silenced by shRNA expression. Effects of silencing and Rac inhibitors were assessed by CCK-8 assay, EdU staining, RT-PCR, colony formation assay, flow cytometry, and phalloidin staining. KEY FINDINGS Silencing of Rac1 expression reduced the viability (up to 83% compared to scramble shRNA) and proliferation (virtually completely in proliferation assay), increased apoptosis (124%) and the number of dead cells (51%), and caused breakdown of actin organization (56% reduction of polymerized actin compared to scramble shRNA). Effects on proliferation, viability, and actin organization were mimicked by NSC23766 and EHT1864, while both compounds showed divergent effects on cell death (32-fold increase of dead cells by EHT1864, but not NSC23766). Effects of NSC23766 and EHT1864 on viability of hBSMCs were not altered by Rac1 knockdown. SIGNIFICANCE Rac1 promotes proliferation, viability, and cytoskeletal organization, and suppresses apoptosis in bladder smooth muscle cells, which may be relevant in overactive bladder or diabetes-related bladder dysfunction. NSC23766 and EHT1864 mimick these effects, but may act Rac1-independently, by shared and divergent effects.
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7
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Peng HY, Lai CY, Hsieh MC, Ho YC, Lin TB. Pressure-volume analysis of rat's micturition cycles in vivo. Neurourol Urodyn 2020; 39:1304-1312. [PMID: 32293055 PMCID: PMC7318613 DOI: 10.1002/nau.24363] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Accepted: 04/01/2020] [Indexed: 11/10/2022]
Abstract
AIMS Though the pressure-volume analysis (PVA), a method based on thermodynamics, is broadly used for assaying cardiac functions, its potential application on the physiology/pathophysiology of the urinary bladder, which processes resemble thermodynamic cycles to the heart, has not been established. METHODS Cystometry recording intravesical pressure (IVP) and intravesical volume (IVV) of rhythmic voiding contractions caused by a constant saline infusion (0.04 mL/min) were carried out in forty urethane-anesthetized female Sprague-Dawley rats, and the PVA was established by plotting IVP against IVV. RESULTS Pressure-volume points shaped coincident enclosed loops, and loop-associated urodynamic parameters kept stable under a constant infusion rate (0.04 mL/min). Enhancing preload (by elevating infusion rates to 0.08 and 0.12 mL/min) increased the area enclosed by the loop (Apv) and shifted loops to the right and slightly upward. Augmenting afterload (by enhancing resistances using 1/4 and 1/2 urethra clamping) increased Apv and shifted loops markedly to the right and upward. Without affecting Apv, muscarine (0.01 and 0.1 mM)-induced inotropic states shifted loop to the left and upward that was as opposed to the atropine (0.01 and 0.1 mM)-induced anti-inotropic state. CONCLUSIONS Not only consistently assayed baseline bladder functions, PVA but also validly measured modified bladder functions due to altered extrinsic environment and intrinsic contractility of the bladder itself. In accompanied by cystometry, PVA could provide a clear concept about the relationship between time, pressure, and volume in the voiding activity.
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Affiliation(s)
- Hsien-Yu Peng
- Department of Medicine, Mackay Medical College, New Taipei, Taiwan
| | - Cheng-Yuan Lai
- Department of Medicine, Mackay Medical College, New Taipei, Taiwan
| | - Ming-Chun Hsieh
- Department of Medicine, Mackay Medical College, New Taipei, Taiwan
| | - Yu-Cheng Ho
- Department of Medicine, Mackay Medical College, New Taipei, Taiwan
| | - Tzer-Bin Lin
- Department of Physiology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan.,Cell Physiology and Molecular Image Research Center, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan.,Department of Biotechnology, College of Medical and Health Science, Asia University, Taichung, Taiwan
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8
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Li B, Yu Q, Wang R, Gratzke C, Wang X, Spek A, Herlemann A, Tamalunas A, Strittmatter F, Waidelich R, Stief CG, Hennenberg M. Inhibition of Female and Male Human Detrusor Smooth Muscle Contraction by the Rac Inhibitors EHT1864 and NSC23766. Front Pharmacol 2020; 11:409. [PMID: 32317972 PMCID: PMC7154109 DOI: 10.3389/fphar.2020.00409] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Accepted: 03/18/2020] [Indexed: 12/14/2022] Open
Abstract
Introduction Lower urinary tract symptoms (LUTS) due to overactive bladder (OAB) are caused by spontaneous detrusor contractions. Medical treatment with muscarinic receptor antagonists or β3-adrenoceptor agonists aims to inhibit detrusor contractions, but overall results are unsatisfactory. Consequently, improved understanding of bladder smooth muscle contraction and identification of novel compounds for its inhibition are needed to develop alternative options. A role of the GTPase Rac1 for smooth muscle contraction has been reported from the prostate, but is unknown in the human detrusor. Here, we examined effects of the Rac inhibitors NSC23766, which may also antagonize muscarinic receptors, and EHT1864 on contraction of human detrusor tissues. Methods Female and male human detrusor tissues were obtained from radical cystectomy. Effects of NSC23766 (100 µM) and EHT1864 (100 µM) on detrusor contractions were studied in an organ bath. Results Electric field stimulation induced frequency-dependent contractions of detrusor tissues, which were inhibited by NSC23766 and EHT1864. Carbachol induced concentration-dependent contractions. Concentration response curves for carbachol were shifted to the right by NSC23766, reflected by increased EC50 values, but unchanged Emax values. EHT1864 reduced carbachol-induced contractions, resulting in reduced Emax values for carbachol. The thromboxane analog U46619 induced concentration-dependent contractions, which remained unchanged by NSC23766, but were reduced by EHT1864. Conclusions NSC23766 and EHT1864 inhibit female and male human detrusor contractions. NSC23766, but not EHT1864 competitively antagonizes muscarinic receptors. In addition to neurogenic and cholinergic contractions, EHT1864 inhibits thromboxane A2-induced detrusor contractions. The latter may be promising, as the origin of spontaneous detrusor contractions in OAB is noncholinergic. In vivo, both compounds may improve OAB-related LUTS.
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Affiliation(s)
- Bingsheng Li
- Department of Urology, University Hospital, LMU Munich, Munich, Germany
| | - Qingfeng Yu
- Department of Urology, University Hospital, LMU Munich, Munich, Germany
| | - Ruixiao Wang
- Department of Urology, University Hospital, LMU Munich, Munich, Germany
| | - Christian Gratzke
- Department of Urology, University Hospital, LMU Munich, Munich, Germany.,Department of Urology, University of Freiburg, Freiburg, Germany
| | - Xiaolong Wang
- Department of Urology, University Hospital, LMU Munich, Munich, Germany
| | - Annabel Spek
- Department of Urology, University Hospital, LMU Munich, Munich, Germany
| | - Annika Herlemann
- Department of Urology, University Hospital, LMU Munich, Munich, Germany
| | | | | | | | - Christian G Stief
- Department of Urology, University Hospital, LMU Munich, Munich, Germany
| | - Martin Hennenberg
- Department of Urology, University Hospital, LMU Munich, Munich, Germany
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Li B, Wang X, Rutz B, Wang R, Tamalunas A, Strittmatter F, Waidelich R, Stief CG, Hennenberg M. The STK16 inhibitor STK16-IN-1 inhibits non-adrenergic and non-neurogenic smooth muscle contractions in the human prostate and the human male detrusor. Naunyn Schmiedebergs Arch Pharmacol 2019; 393:829-842. [PMID: 31867686 DOI: 10.1007/s00210-019-01797-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Accepted: 12/12/2019] [Indexed: 01/25/2023]
Abstract
Mixed lower urinary tract symptoms (LUTS) (voiding symptoms suggestive of benign prostatic hyperplasia plus storage symptoms, which can be caused by overactive bladder) are common in men. Unwanted contraction of prostate and/or bladder smooth muscle has been implied in the pathophysiology of male LUTS. Here, we examined effects of the serine/threonine kinase 16 (STK16) inhibitor STK16-IN-1 on contraction of human tissues from the prostate and male detrusor. Tissues were obtained from radical prostatectomy and radical cystectomy. Contractions were studied in an organ bath and STK16 expressions by Western blot analyses and fluorescence staining. In prostate tissues, STK16-IN-1 (1 μM) inhibited contractions induced by endothelin-1 and the thromboxane A2 analog U46619. Contractions of prostate tissues induced by noradrenaline, the α1-agonists phenylephrine and methoxamine, or electric field stimulation (EFS) were not changed by STK16-IN-1. In male detrusor tissues, STK16-IN-1 inhibited contractions induced by the cholinergic agonists carbachol and metacholine, and contractions induced by U46619. EFS-induced contractions of detrusor tissues were not changed by STK16-IN-1. Western blot analyses of prostate and detrusor tissues revealed bands matching the molecular weight of STK16. Fluorescence staining of prostate tissues using STK16 antibodies resulted in immunoreactivity in smooth muscle cells. STK16-IN-1 selectively inhibits non-adrenergic/non-neurogenic smooth muscle contractions in the male prostate and to limited extent in the bladder. Because non-adrenergic contractions in the male LUTS may account for limited efficacy of α1-blockers and for α1-blocker-resistant symptoms, studies assessing add-on of STK16-IN-1 to α1-blockers in mixed LUTS appear feasible.
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Affiliation(s)
- Bingsheng Li
- Department of Urology, University Hospital, LMU Munich, Munich, Germany
| | - Xiaolong Wang
- Department of Urology, University Hospital, LMU Munich, Munich, Germany
| | - Beata Rutz
- Department of Urology, University Hospital, LMU Munich, Munich, Germany
| | - Ruixiao Wang
- Department of Urology, University Hospital, LMU Munich, Munich, Germany
| | | | | | | | - Christian G Stief
- Department of Urology, University Hospital, LMU Munich, Munich, Germany
| | - Martin Hennenberg
- Department of Urology, University Hospital, LMU Munich, Munich, Germany. .,Urologische Klinik und Poliklinik, LMU Munich, Marchioninistr. 15, 81377, Munich, Germany.
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McCarthy CJ, Ikeda Y, Skennerton D, Chakrabarty B, Kanai AJ, Jabr RI, Fry CH. Characterisation of nerve-mediated ATP release from bladder detrusor muscle and its pathological implications. Br J Pharmacol 2019; 176:4720-4730. [PMID: 31430833 DOI: 10.1111/bph.14840] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Revised: 07/31/2019] [Accepted: 08/04/2019] [Indexed: 11/26/2022] Open
Abstract
BACKGROUND AND PURPOSE This study aims to characterise the molecular mechanisms that determine variability of atropine resistance of nerve-mediated contractions in human and guinea pig detrusor smooth muscle. EXPERIMENTAL APPROACH Atropine resistance of nerve-mediated contractions and the role of P2X1 receptors, were assessed in isolated preparations from guinea pigs and also humans with or without overactive bladder syndrome, from which the mucosa was removed. Nerve-mediated ATP release was measured directly with amperometric ATP-sensitive electrodes. Ecto-ATPase activity of guinea pig and human detrusor samples was measured in vitro by measuring the concentration-dependent rate of ATP breakdown. The transcription of ecto-ATPase subtypes in human samples was measured by qPCR. KEY RESULTS Atropine resistance was greatest in guinea pig detrusor, absent in human tissue from normally functioning bladders, and intermediate in human overactive bladder. Greater atropine resistance correlated with reduction of contractions by the ATP-diphosphohydrolase apyrase, directly implicating ATP in their generation. E-NTPDase-1 was the most abundantly transcribed ecto-ATPase of those tested, and transcription was reduced in tissue from human overactive, compared to normal, bladders. E-NTPDase-1 enzymic activity was inversely related to the magnitude of atropine resistance. Nerve-mediated ATP release was continually measured and varied with stimulation frequency over the range of 1-16 Hz. CONCLUSION AND IMPLICATIONS Atropine resistance in nerve-mediated detrusor contractions is due to ATP release and its magnitude is inversely related to E-NTPDase-1 activity. ATP is released under different stimulation conditions compared with ACh, implying different routes for their release.
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Affiliation(s)
- Carly J McCarthy
- Instituto de Investigaciones en Medicina Traslacional (IIMT), Facultad de Ciencias Biomédicas, Austral University, Buenos Aires, Argentina.,Department of Surgery, University College London, London, UK
| | - Youko Ikeda
- Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania.,Department of Surgery, University College London, London, UK
| | | | - Basu Chakrabarty
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, UK
| | - Anthony J Kanai
- Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Rita I Jabr
- School of Biosciences and Medicine, University of Surrey, Surrey, UK
| | - Christopher H Fry
- Department of Surgery, University College London, London, UK.,School of Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, UK
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11
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McCarthy CJ, Marangos C, Fry CH, Ikeda Y. ATP transients accompany spontaneous contractions in isolated guinea-pig detrusor smooth muscle. Exp Physiol 2019; 104:1717-1725. [PMID: 31464344 DOI: 10.1113/ep087960] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Accepted: 08/21/2019] [Indexed: 11/08/2022]
Abstract
NEW FINDINGS What is the central question of this study? Overactive bladder is associated with enhanced spontaneous contractions, but their origins are unclear. The aim of this study was to characterize the accompanying ATP transients. What is the main finding and its importance? Spontaneous detrusor contractions were accompanied by transient increases of ATP, and their appearance was delayed by previous activation of efferent nerves to the detrusor. This indicates that spontaneous ATP release from nerve terminals supports spontaneous contractions. ATP is a functional excitatory neurotransmitter in human bladder only in pathologies such as overactive bladder. A potential drug target is revealed to manage this condition. ABSTRACT Spontaneous contractions are characteristic of the bladder wall, but their origins remain unclear. Activity is reduced if the mucosa is removed but does not disappear, suggesting that a fraction arises from the detrusor. We tested the hypothesis that spontaneous detrusor contractions arise from spontaneous ATP release. Guinea-pig detrusor strips, without mucosa, were superfused with Tyrode solution at 36°C. Preparations were subjected to electrical field stimulation (EFS; 3 s trains at 90 s intervals) to produce nerve-mediated contractions, abolished by 1 µm TTX. Amperometric ATP electrodes on the preparation surface recorded any ATP released. Spontaneous contractions and ATP transients were recorded between EFS trains. Nerve-mediated contractions were attenuated by atropine and α,β-methylene ATP; in combination, they nearly abolished contractions, as did nifedipine. Contractions were accompanied by ATP transients that were unaffected by atropine but inhibited by TTX and greatly attenuated by nifedipine. Spontaneous contractions were accompanied by ATP transients, with a close correlation between the magnitudes of both transients. ATP and contractile transients persisted with TTX, atropine and nifedipine. Immediately after a nerve-mediated contraction and ATP transient, there was a longer interval than normal before spontaneous activity resumed. Spontaneous contractions and ATP transients are proposed to arise from ATP leakage from nerve terminals innervating the detrusor. Extracellular ATP has a greater functional significance in humans who suffer from detrusor overactivity (spontaneous bladder contractions associated with incontinence) owing to its reduced hydrolysis at the nerve-muscle interface. This study shows the origin of spontaneous activity that might be exploited to develop a therapeutic management of this condition.
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Affiliation(s)
- Carly J McCarthy
- Instituto de Investigaciones en Medicina Traslacional (IIMT), Facultad de Ciencias Biomédicas, Austral University, Pilar Centro, Buenos Aires, Argentina
| | | | - Christopher H Fry
- School of Physiology, Pharmacology & Neuroscience, University of Bristol, Bristol, UK.,Institute of Child Health, University College London, London, UK
| | - Youko Ikeda
- Department of Medicine, University of Pittsburgh, Pittsburgh, PA, USA
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12
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Mitsui R, Lee K, Uchiyama A, Hayakawa S, Kinoshita F, Kajioka S, Eto M, Hashitani H. Contractile elements and their sympathetic regulations in the pig urinary bladder: a species and regional comparative study. Cell Tissue Res 2019; 379:373-387. [PMID: 31446446 DOI: 10.1007/s00441-019-03088-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Accepted: 08/05/2019] [Indexed: 12/18/2022]
Abstract
Contractile behaviour of the urinary bladder and its sympathetic inhibition during storage phases are not well understood. Here, we explore muscularis mucosae (MM) as a predominant mucosal contractile element and the capability of sympathetic nerves to relax detrusor smooth muscle (DSM) or MM. Distribution of α-smooth muscle actin (α-SMA)-immunoreactive cells was compared in pig, human, guinea pig, rat and mouse bladders by immunohistochemistry, while contractility of the bladder mucosa was compared in these species by isometric tension recordings. In pig, human and guinea pig bladders, DSM and MM located in the lamina propria expressed α-SMA immunoreactivity, while both rat and mouse bladders lacked a MM. Consistent with this presence or absence of MM, bladder mucosa of pig, human and guinea pig but not rat and mouse developed spontaneous phasic contractions (SPCs). Distribution of tyrosine hydroxylase (TH)-immunoreactive sympathetic nerve fibres was compared in pig DSM, MM, trigone and urethra, as were their sympathetic nerve-evoked contractile/relaxing responses examined. In pig DSM or MM, where TH-immunoreactive sympathetic fibres exclusively projected to the vasculature, sympathetic relaxations were difficult to demonstrate. In contrast, sympathetic contractions were invariably evoked in pig trigone and urethra where the smooth muscle cells receive TH-immunoreactive sympathetic innervations. Thus, SPCs of bladder mucosa appear to predominantly arise from the MM displaying species differences. Despite the currently accepted concept of sympathetic nerve-mediated DSM relaxation during the storage phase, it is unlikely that neurally released noradrenaline acts on β-adrenoceptors to relax either DSM or MM due to the anatomical lack of sympathetic innervation.
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Affiliation(s)
- Retsu Mitsui
- Department of Cell Physiology, Nagoya City University Graduate School of Medical Sciences, Nagoya, 467-8601, Japan.
| | - Ken Lee
- Department of Urology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Aoi Uchiyama
- Department of Cell Physiology, Nagoya City University Graduate School of Medical Sciences, Nagoya, 467-8601, Japan
| | - Shunta Hayakawa
- Department of Cell Physiology, Nagoya City University Graduate School of Medical Sciences, Nagoya, 467-8601, Japan
| | - Fumio Kinoshita
- Department of Anatomic Pathology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Shunichi Kajioka
- Department of Applied Urology and Molecular Medicine, Kyushu University, Fukuoka, Japan
| | - Masatoshi Eto
- Department of Urology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Hikaru Hashitani
- Department of Cell Physiology, Nagoya City University Graduate School of Medical Sciences, Nagoya, 467-8601, Japan
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13
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Fry CH, McCloskey KD. Spontaneous Activity and the Urinary Bladder. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1124:121-147. [PMID: 31183825 DOI: 10.1007/978-981-13-5895-1_5] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The urinary bladder has two functions: to store urine, when it is relaxed and highly compliant; and void its contents, when intravesical pressure rises due to co-ordinated contraction of detrusor smooth muscle in the bladder wall. Superimposed on this description are two observations: (1) the normal, relaxed bladder develops small transient increases of intravesical pressure, mirrored by local bladder wall movements; (2) pathological, larger pressure variations (detrusor overactivity) can occur that may cause involuntary urine loss and/or detrusor overactivity. Characterisation of these spontaneous contractions is important to understand: how normal bladder compliance is maintained during filling; and the pathophysiology of detrusor overactivity. Consideration of how spontaneous contractions originate should include the structural complexity of the bladder wall. Detrusor smooth muscle layer is overlain by a mucosa, itself a complex structure of urothelium and a lamina propria containing sensory nerves, micro-vasculature, interstitial cells and diffuse muscular elements.Several theories, not mutually exclusive, have been advanced for the origin of spontaneous contractions. These include intrinsic rhythmicity of detrusor muscle; modulation by non-muscular pacemaking cells in the bladder wall; motor input to detrusor by autonomic nerves; regulation of detrusor muscle excitability and contractility by the adjacent mucosa and spontaneous contraction of elements of the lamina propria. This chapter will consider evidence for each theory in both normal and overactive bladder and how their significance may vary during ageing and development. Further understanding of these mechanisms may also identify novel drug targets to ameliorate the clinical consequences of large contractions associated with detrusor overactivity.
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Affiliation(s)
- Christopher H Fry
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, UK.
| | - Karen D McCloskey
- School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, UK
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14
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Chakrabarty B, Ito H, Ximenes M, Nishikawa N, Vahabi B, Kanai AJ, Pickering AE, Drake MJ, Fry CH. Influence of sildenafil on the purinergic components of nerve-mediated and urothelial ATP release from the bladder of normal and spinal cord injured mice. Br J Pharmacol 2019; 176:2227-2237. [PMID: 30924527 PMCID: PMC6555867 DOI: 10.1111/bph.14669] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2018] [Revised: 02/21/2019] [Accepted: 03/12/2019] [Indexed: 01/19/2023] Open
Abstract
Background and purpose PDE inhibitors such as sildenafil alleviate lower urinary tract symptoms; however, a complete understanding of their action on the bladder remains unclear. We are investigating the effects of sildenafil, on post and preganglionic nerve‐mediated contractions of the mouse bladder, and neuronal and urothelial ATP release. Experimental approach Bladders were used from young (12 weeks), aged (24 months), and spinal cord transected (SCT), mice, for in vitro contractility experiments. An arterially perfused in situ whole mouse model was used to record bladder pressure. Nerve‐mediated contractions were generated by electrical field stimulation (EFS) of postganglionic nerve terminals or the pelvic nerve. ATP release during EFS in intact detrusor strips, and during stretch of isolated mucosa strips, was measured using a luciferin‐luciferase assay. Key results Sildenafil (20 μM) inhibited nerve‐mediated contractions in young mice, with an increase in f1/2 values in force–frequency relationships, demonstrating a greater effect at low frequencies. Sildenafil reduced the atropine‐resistant, purinergic component of nerve‐mediated contractions, and suppressed neuronal ATP release upon EFS in vitro. Sildenafil reduced the preganglionic pelvic nerve stimulated bladder pressure recordings in situ; comparable to in vitro experiments. Sildenafil reduced stretch‐induced urothelial ATP release. Sildenafil also relaxed nerve‐mediated contractions in aged and SCT mice. Conclusion and implications Sildenafil has a greater effect on the low‐frequency, purinergic‐mediated contractions and suppresses neuronal ATP release. In addition, sildenafil reduces stretch‐induced urothelial ATP release. These results demonstrate a novel action of sildenafil to selectively inhibit ATP release from nerve terminals innervating detrusor smooth muscle and the urothelium.
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Affiliation(s)
- Basu Chakrabarty
- School of Physiology, Pharmacology, and Neuroscience, University of Bristol, Bristol, UK
| | - Hiroki Ito
- School of Physiology, Pharmacology, and Neuroscience, University of Bristol, Bristol, UK
| | - Manuela Ximenes
- School of Physiology, Pharmacology, and Neuroscience, University of Bristol, Bristol, UK.,Department of Applied Sciences, University of West England, Bristol, UK
| | - Nobuyuki Nishikawa
- School of Physiology, Pharmacology, and Neuroscience, University of Bristol, Bristol, UK
| | - Bahareh Vahabi
- School of Physiology, Pharmacology, and Neuroscience, University of Bristol, Bristol, UK.,Department of Applied Sciences, University of West England, Bristol, UK
| | - Anthony J Kanai
- Departments of Medicine and Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Anthony E Pickering
- School of Physiology, Pharmacology, and Neuroscience, University of Bristol, Bristol, UK.,Translational Health Sciences, Bristol Medical School, University of Bristol, Bristol, UK
| | - Marcus J Drake
- Translational Health Sciences, Bristol Medical School, University of Bristol, Bristol, UK.,Bristol Urological Institute, Southmead Hospital, Bristol, UK
| | - Christopher H Fry
- School of Physiology, Pharmacology, and Neuroscience, University of Bristol, Bristol, UK
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15
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Igawa Y, Aizawa N, Michel MC. β 3 -Adrenoceptors in the normal and diseased urinary bladder-What are the open questions? Br J Pharmacol 2019; 176:2525-2538. [PMID: 30868554 DOI: 10.1111/bph.14658] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Revised: 12/31/2018] [Accepted: 01/29/2019] [Indexed: 12/13/2022] Open
Abstract
β3 -Adrenoceptor agonists are used in the treatment of overactive bladder syndrome. Although the relaxant response to adrenergic stimulation in human detrusor smooth muscle cells is mediated mainly via β3 -adrenoceptors, the plasma concentrations of the therapeutic dose of mirabegron, the only clinically approved β3 -adrenoceptor agonist, are considerably lower than the EC50 for causing direct relaxation of human detrusor, suggesting a mechanism of action other than direct relaxation of detrusor smooth muscle. However, the site and mechanism of action of β3 -adrenoceptor agonists in the bladder have not been firmly established. Postulated mechanisms include prejunctional suppression of ACh release from the parasympathetic nerves during the storage phase and inhibition of micro-contractions through β3 -adrenoceptors on detrusor smooth muscle cells or suburothelial interstitial cells. Implications of possible desensitization of β3 -adrenoceptors in the bladder upon prolonged agonist exposure and possible causes of rarely observed cardiovascular effects of mirabegron are also discussed. LINKED ARTICLES: This article is part of a themed section on Adrenoceptors-New Roles for Old Players. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v176.14/issuetoc.
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Affiliation(s)
- Yasuhiko Igawa
- Department of Continence Medicine, The University of Tokyo Graduate School of Medicine, Tokyo, Japan
| | - Naoki Aizawa
- Department of Continence Medicine, The University of Tokyo Graduate School of Medicine, Tokyo, Japan
| | - Martin C Michel
- Department of Pharmacology, Johannes Gutenberg University, Mainz, Germany
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16
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Peyronnet B, Mironska E, Chapple C, Cardozo L, Oelke M, Dmochowski R, Amarenco G, Gamé X, Kirby R, Van Der Aa F, Cornu JN. A Comprehensive Review of Overactive Bladder Pathophysiology: On the Way to Tailored Treatment. Eur Urol 2019; 75:988-1000. [PMID: 30922690 DOI: 10.1016/j.eururo.2019.02.038] [Citation(s) in RCA: 180] [Impact Index Per Article: 36.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2018] [Accepted: 02/28/2019] [Indexed: 01/06/2023]
Abstract
CONTEXT Current literature suggests that several pathophysiological factors and mechanisms might be responsible for the nonspecific symptom complex of overactive bladder (OAB). OBJECTIVE To provide a comprehensive analysis of the potential pathophysiology underlying detrusor overactivity (DO) and OAB. EVIDENCE ACQUISITION A PubMed-based literature search was conducted in April 2018, to identify randomised controlled trials, prospective and retrospective series, animal model studies, and reviews. EVIDENCE SYNTHESIS OAB is a nonspecific storage symptom complex with poorly defined pathophysiology. OAB was historically thought to be caused by DO, which was either "myogenic" (urgency initiated from autonomous contraction of the detrusor muscle) or "neurogenic" (urgency signalled from the central nervous system, which initiates a detrusor contraction). Patients with OAB are often found to not have objective evidence of DO on urodynamic studies; therefore, alternative mechanisms for the development of OAB have been postulated. Increasing evidence on the role of urothelium/suburothelium and bladder afferent signalling arose in the early 2000s, emphasising an afferent "urotheliogenic" hypothesis, namely, that urgency is initiated from the urothelium/suburothelium. The urethra has also recently been regarded as a possible afferent origin of OAB-the "urethrogenic" hypothesis. Several other pathophysiological factors have been implicated, including metabolic syndrome, affective disorders, sex hormone deficiency, urinary microbiota, gastrointestinal functional disorders, and subclinical autonomic nervous system dysfunctions. These various possible mechanisms should be considered as contributing to diagnostic and treatment algorithms. CONCLUSIONS There is a temptation to label OAB as "idiopathic" without obvious causation, given the poorly understood nature of its pathophysiology. OAB should be seen as a complex, multifactorial symptom syndrome, resulting from multiple potential pathophysiological mechanisms. Identification of the underlying causes on an individual basis may lead to the definition of OAB phenotypes, paving the way for personalised medical care. PATIENT SUMMARY Overactive bladder (OAB) is a storage symptom syndrome with multiple possible causes. Identification of the mechanisms causing a patient to experience OAB symptoms may help tailor treatment to individual patients and improve outcomes.
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Affiliation(s)
- Benoit Peyronnet
- Department of Urology, University Hospital of Rennes, Rennes, France.
| | - Emma Mironska
- Department of Urology, Sheffield Teaching Hospitals, Sheffield, UK
| | | | - Linda Cardozo
- Department of Urology, St. Antonius Hospital, Gronau, Germany
| | - Matthias Oelke
- Department of Urology, Vanderbilt University, Nashville, TN, USA
| | | | - Gérard Amarenco
- Department of Urogynaecology, King's College Hospital, London, UK
| | - Xavier Gamé
- Department of Urology, University Hospital of Toulouse, Toulouse, France
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17
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Doyle C, Cristofaro V, Sack BS, Mahmood F, Sullivan MP, Adam RM. The role of the mucosa in modulation of evoked responses in the spinal cord injured rat bladder. Neurourol Urodyn 2018; 37:1583-1593. [PMID: 29427331 PMCID: PMC6086770 DOI: 10.1002/nau.23512] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2017] [Accepted: 01/09/2018] [Indexed: 11/27/2022]
Abstract
Aims Mounting evidence indicates that a variety of factors released from the urothelium or suburothelium can modulate smooth muscle activity. Although the relationship between the mucosa and smooth muscle has been investigated, little is known about the pathophysiologic changes in detrusor‐mucosa interactions in neurogenic bladders. The goal of the study was to determine the impact of the mucosa on evoked responses in spinal cord injured (SCI) bladders. Methods Urinary bladders were obtained from 6wk SCI rats or age‐matched uninjured controls. Ex vivo isometric tension studies were performed and muscarinic receptor expression was measured in bladder tissue with and without mucosa. Results The magnitude and area of nerve evoked responses in SCI tissue with mucosa was higher than without mucosa. The duration and decay time of nerve‐evoked responses were longer in SCI than control tissue irrespective of the mucosa. The level of the muscarinic M2 receptor was decreased in the mucosa of SCI bladders. Conclusions Detrusor‐mucosa interactions are substantially altered in the neurogenic bladder. After spinal cord injury, an excitatory modulation of smooth muscle contraction by the mucosa emerges, and could be targeted via intravesical treatment in the context of neurogenic bladder dysfunction.
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Affiliation(s)
- Claire Doyle
- Urological Diseases Research Center, Boston Children's Hospital, Boston, Massachusetts.,Department of Surgery, Harvard Medical School, Boston, Massachusetts
| | - Vivian Cristofaro
- Department of Surgery, Harvard Medical School, Boston, Massachusetts.,Division of Urology, VA Boston Healthcare System, Boston, Massachusetts.,Department of Surgery, Brigham and Women's Hospital, Boston, Massachusetts
| | - Bryan S Sack
- Urological Diseases Research Center, Boston Children's Hospital, Boston, Massachusetts.,Department of Surgery, Harvard Medical School, Boston, Massachusetts
| | - Fabliha Mahmood
- Urological Diseases Research Center, Boston Children's Hospital, Boston, Massachusetts
| | - Maryrose P Sullivan
- Department of Surgery, Harvard Medical School, Boston, Massachusetts.,Division of Urology, VA Boston Healthcare System, Boston, Massachusetts.,Department of Surgery, Brigham and Women's Hospital, Boston, Massachusetts
| | - Rosalyn M Adam
- Urological Diseases Research Center, Boston Children's Hospital, Boston, Massachusetts.,Department of Surgery, Harvard Medical School, Boston, Massachusetts
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18
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Drake MJ, Fry CH, Hashitani H, Kirschner-Hermanns R, Rahnama'i MS, Speich JE, Tomoe H, Kanai AJ, McCloskey KD. What are the origins and relevance of spontaneous bladder contractions? ICI-RS 2017. Neurourol Urodyn 2018; 37:S13-S19. [PMID: 29360173 DOI: 10.1002/nau.23485] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Accepted: 12/14/2017] [Indexed: 12/16/2022]
Abstract
INTRODUCTION Storage phase bladder activity is a counter-intuitive observation of spontaneous contractions. They are potentially an intrinsic feature of the smooth muscle, but interstitial cells in the mucosa and the detrusor itself, as well as other muscular elements in the mucosa may substantially influence them. They are identified in several models explaining lower urinary tract dysfunction. METHODS A consensus meeting at the International Consultation on Incontinence Research Society (ICI-RS) 2017 congress considered the origins and relevance of spontaneous bladder contractions by debating which cell type(s) modulate bladder spontaneous activity, whether the methodologies are sufficiently robust, and implications for healthy and abnormal lower urinary tract function. RESULTS The identified research priorities reflect a wide range of unknown aspects. Cellular contributions to spontaneous contractions in detrusor smooth muscle are still uncertain. Accordingly, insight into the cellular physiology of the bladder wall, particularly smooth muscle cells, interstitial cells, and urothelium, remains important. Upstream influences, such as innervation, endocrine, and paracrine factors, are particularly important. The cellular interactions represent the key understanding to derive the integrative physiology of organ function, notably the nature of signalling between mucosa and detrusor layers. Indeed, it is still not clear to what extent spontaneous contractions generated in isolated preparations mirror their normal and pathological counterparts in the intact bladder. Improved models of how spontaneous contractions influence pressure generation and sensory nerve function are also needed. CONCLUSIONS Deriving approaches to robust evaluation of spontaneous contractions and their influences for experimental and clinical use could yield considerable progress in functional urology.
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Affiliation(s)
- Marcus J Drake
- Translational Health Sciences, Bristol Medical School, University of Bristol, Bristol, United Kingdom.,Bristol Urological Institute, Southmead Hospital, Bristol, United Kingdom
| | - Christopher H Fry
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, United Kingdom
| | - Hikaru Hashitani
- Department of Cell Physiology, Graduate School of Medical Sciences, Nagoya City University, Nagoya, Japan
| | - Ruth Kirschner-Hermanns
- Neuro-Urology/Urology, University Clinic, Rheinische Friedrich Wilhelms University Bonn and Neurological Rehabilitation Center Godeshöhe, Bonn, Germany
| | | | - John E Speich
- Department of Mechanical and Nuclear Engineering, Virginia Commonwealth University, Richmond, Virginia
| | - Hikaru Tomoe
- Department of Urology and Pelvic Reconstructive Surgery, Tokyo Women's Medical University Medical Center East, Tokyo, Japan
| | - Anthony J Kanai
- Department of Medicine, Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Karen D McCloskey
- Centre for Cancer Research and Cell Biology, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, United Kingdom
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19
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Ito H, Drake MJ, Fry CH, Kanai AJ, Pickering AE. Characterization of mouse neuro-urological dynamics in a novel decerebrate arterially perfused mouse (DAPM) preparation. Neurourol Urodyn 2018; 37:1302-1312. [PMID: 29333621 PMCID: PMC5947622 DOI: 10.1002/nau.23471] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2017] [Accepted: 11/20/2017] [Indexed: 12/18/2022]
Abstract
AIM To develop the decerebrate arterially perfused mouse (DAPM) preparation, a novel voiding model of the lower urinary tract (LUT) that enables in vitro-like access with in vivo-like neural connectivity. METHODS Adult male mice were decerebrated and arterially perfused with a carbogenated, Ringer's solution to establish the DAPM. To allow distinction between central and peripheral actions of interventions, experiments were conducted in both the DAPM and in a "pithed" DAPM which has no brainstem or spinal cord control. RESULTS Functional micturition cycles were observed in response to bladder filling. During each void, the bladder showed strong contractions and the external urethral sphincter (EUS) showed bursting activity. Both the frequency and amplitude of non-voiding contractions (NVCs) in DAPM and putative micromotions (pMM) in pithed DAPM increased with bladder filling. Vasopressin (>400 pM) caused dyssynergy of the LUT resulting in retention in DAPM as it increased tonic EUS activity and basal bladder pressure in a dose-dependent manner (basal pressure increase also noted in pithed DAPM). Both neuromuscular blockade (vecuronium) and autonomic ganglion blockade (hexamethonium), initially caused incomplete voiding, and both drugs eventually stopped voiding in DAPM. Intravesical acetic acid (0.2%) decreased the micturition interval. Recordings from the pelvic nerve in the pithed DAPM showed bladder distention-induced activity in the non-noxious range which was associated with pMM. CONCLUSIONS This study demonstrates the utility of the DAPM which allows a detailed characterization of LUT function in mice.
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Affiliation(s)
- Hiroki Ito
- School of Physiology, Pharmacology and Neuroscience, Faculty of Biomedical Sciences, University of Bristol, Bristol, United Kingdom
| | - Marcus J Drake
- School of Physiology, Pharmacology and Neuroscience, Faculty of Biomedical Sciences, University of Bristol, Bristol, United Kingdom
| | - Christopher H Fry
- School of Physiology, Pharmacology and Neuroscience, Faculty of Biomedical Sciences, University of Bristol, Bristol, United Kingdom
| | - Anthony J Kanai
- Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Anthony E Pickering
- School of Physiology, Pharmacology and Neuroscience, Faculty of Biomedical Sciences, University of Bristol, Bristol, United Kingdom
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20
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Kitney DG, Jabr RI, Vahabi B, Fry CH. Mild external heating and reduction in spontaneous contractions of the bladder. BJU Int 2017; 120:724-730. [PMID: 28609582 PMCID: PMC5643226 DOI: 10.1111/bju.13933] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVES To measure the effect of external heating on bladder wall contractile function, histological structure and expression of proteins related to tissue protection and apoptosis. MATERIAL AND METHODS In vitro preparations of bladder wall and ex vivo perfused pig bladders were heated from 37 to 42°C, 46 and 50°C for 15 min. Isolated preparations were heated by radiant energy and perfused bladders were heated by altering perfusate temperature. Spontaneous contractions or pressure variations were recorded, as well as responses to the muscarinic agonist carbachol or motor nerve excitation in vitro during heating. Tissue histology in control and after heating was analysed using haematoxylin and eosin staining and 4'-6-diamidino-2-phenylindole (DAPI) nuclear labelling. The effects of heating on protein expression levels of (i) heat shock proteins HSP27-pSer82 and inducible-HSP70 and (ii) caspase-3 and its downstream DNA-repair substrate poly-[ADP-ribose] polymerase (PARP) were measured. RESULTS Heating to 42°C reduced spontaneous contractions or pressure variations by ~70%; effects were fully reversible. There were no effects on carbachol or nerve-mediated responses. Tissue histology was unaffected by heating, and expression of heat shock proteins as well as caspase-3 and PARP were also unaltered. A TRPV1 antagonist had no effect on the reduction of spontaneous activity. Heating to 46°C had a similar effect on spontaneous activity and also reduced the carbachol contracture. Urothelial structure was damaged, caspase-3 levels were increased and inducible-HSP70 levels declined. At 50°C evoked contractions were abolished, the urothelium was absent and heat shock proteins and PARP expression was reduced with raised caspase-3 expression. CONCLUSIONS Heating to 42°C caused a profound, reversible and reproducible attenuation of spontaneous activity, with no tissue damage and no initiation of apoptosis pathways. Higher temperatures caused tissue damage and activation of apoptotic mechanisms. Mild heating offers a novel approach to reducing bladder spontaneous activity.
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Affiliation(s)
- Darryl G Kitney
- Faculty of Health and Medical Sciences, University of Surrey, Guildford, UK
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, UK
| | - Rita I Jabr
- Faculty of Health and Medical Sciences, University of Surrey, Guildford, UK
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, UK
| | - Bahareh Vahabi
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, UK
- Department of Biological, Biomedical and Analytical Sciences, University of the West of England, Bristol, UK
| | - Christopher H Fry
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, UK
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21
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Lee K, Isogai A, Antoh M, Kajioka S, Eto M, Hashitani H. Role of K + channels in regulating spontaneous activity in the muscularis mucosae of guinea pig bladder. Eur J Pharmacol 2017; 818:30-37. [PMID: 29050967 DOI: 10.1016/j.ejphar.2017.10.024] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2017] [Revised: 10/11/2017] [Accepted: 10/13/2017] [Indexed: 12/30/2022]
Abstract
To explore the roles of various K+ channels in regulating the spontaneous activity of bladder muscularis mucosae (MM) that is considered to play an important role in maintaining mucosal function. Effects of K+ channel modulators on electrical and contractile activity in the guinea-pig bladder MM were examined using intracellular microelectrode and isometric tension recording. The MM predominately generated bursting spontaneous action potentials (SAPs) and phasic contractions (SPCs) that were blocked by nifedipine (1µM). NS309 (10µM), a small-conductance Ca2+-activated K+ (SK) channel opener, dramatically prolonged after-hyperpolarisation (AHP) and converted bursting SAPs into individually action potentials in an apamin (100nM)-sensitive manner. Apamin alone increased the number of SAPs during bursts. NS1619 (10µM), a large-conductance Ca2+-activated K+ (BK) channel opener, abolished SAPs in a manner reversed by iberiotoxin (IbTX, 100nM), a BK channel blocker. IbTX alone enlarged SAPs and abolished their AHPs. Flupirtine (10µM), a voltage-dependent K+ channel (Kv7) opener, diminished SAPs in a manner reversed by XE991 (10µM), a Kv7 channel blocker. XE991 alone exerted modest excitatory effects on SAPs. These K+ channel modulators had corresponding effects on SPCs. Bursting SAP firing appears to result from a lower level activation of SK channels in MM than that DSM. BK channels play a predominant role in regulating SAP configuration, while Kv7 channels have only a marginal role. The prevention of bursting SAPs and associated reduction in SPCs upon the pharmacological activation of a reserved population of SK channels may well have a considerable therapeutic potential.
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Affiliation(s)
- Ken Lee
- Department of Cell Physiology, Graduate School of Medical Sciences, Nagoya City University, Nagoya, Japan; Department of Urology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
| | - Ayu Isogai
- Department of Cell Physiology, Graduate School of Medical Sciences, Nagoya City University, Nagoya, Japan
| | - Minori Antoh
- Department of Cell Physiology, Graduate School of Medical Sciences, Nagoya City University, Nagoya, Japan
| | - Shunichi Kajioka
- Department of Applied Urology and Molecular Medicine, Kyushu University, Fukuoka, Japan
| | - Masatoshi Eto
- Department of Urology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Hikaru Hashitani
- Department of Cell Physiology, Graduate School of Medical Sciences, Nagoya City University, Nagoya, Japan
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Takeya M, Hashitani H, Hayashi T, Higashi R, Nakamura KI, Takano M. Role of mucosa in generating spontaneous activity in the guinea pig seminal vesicle. J Physiol 2017; 595:4803-4821. [PMID: 28421606 DOI: 10.1113/jp273872] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Accepted: 04/11/2017] [Indexed: 01/08/2023] Open
Abstract
KEY POINTS The mucosa may have neuron-like functions as urinary bladder mucosa releases bioactive substances that modulate sensory nerve activity as well as detrusor muscle contractility. However, such mucosal function in other visceral organs remains to be established. The role of mucosa in generating spontaneous contractions in seminal vesicles (SVs), a paired organ in the male reproductive tract, was investigated. The intact mucosa is essential for the generation of spontaneous phasic contractions of SV smooth muscle arising from electrical slow waves and corresponding increases in intracellular Ca2+ . These spontaneous events primarily depend on Ca2+ handling by sarco-endoplasmic reticulum Ca2+ stores. A population of mucosal cells developed spontaneous rises in intracellular Ca2+ relying on sarco-endoplasmic reticulum Ca2+ handling. The spontaneously active cells in the SV mucosa appear to drive spontaneous activity in smooth muscle either by sending depolarizing signals and/or by releasing humoral substances. ABSTRACT The role of the mucosa in generating the spontaneous activity of guinea-pig seminal vesicle (SV) was explored. Changes in contractility, membrane potential and intracellular Ca2+ dynamics of SV smooth muscle cells (SMCs) were recorded using isometric tension recording, intracellular microelectrode recording and epi-fluorescence Ca2+ imaging, respectively. Mucosa-intact but not mucosa-denuded SV preparations generated TTX- (1 μm) resistant spontaneous phasic contractions that were abolished by nifedipine (3 μm). Consistently, SMCs developed mucosa-dependent slow waves (SWs) that triggered action potentials and corresponding Ca2+ flashes. Nifedipine (10 μm) abolished the action potentials and spontaneous contractions, while suppressing the SWs and Ca2+ flashes. Both the residual SWs and spontaneous Ca2+ transients were abolished by cyclopiazonic acid (CPA, 10 μm), a sarco-endoplasmic reticulum Ca2+ -ATPase (SERCA) inhibitor. DIDS (300 μm) and niflumic acid (100 μm), blockers for Ca2+ -activated Cl- channels (CACCs), or low Cl- solution also slowed or prevented the generation of SWs. In SV mucosal preparations detached from the muscle layer, a population of mucosal cells generated spontaneous Ca2+ transients that were blocked by CPA but not nifedipine. These results suggested that spontaneous contractions and corresponding Ca2+ flashes in SV SMCs arise from action potential generation due to the opening of L-type voltage-dependent Ca2+ channels. Spontaneous Ca2+ transients appear to primarily result from Ca2+ release from sarco-endoplasmic reticulum Ca2+ stores to activate CACCs to develop SWs. The mucosal cells firing spontaneous Ca2+ transients may play a critical role in driving spontaneous activity of SV smooth muscle either by sending depolarizing signals or by releasing humoral substances.
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Affiliation(s)
- Mitsue Takeya
- Division of Integrated Autonomic Function, Department of Physiology, Kurume University School of Medicine, Kurume, Japan
| | - Hikaru Hashitani
- Department of Cell Physiology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Tokumasa Hayashi
- Department of Urology, Kurume University School of Medicine, Kurume, Japan
| | - Ryuhei Higashi
- Electron Microscopic Laboratory, Central Research Unit of Kurume University School of Medicine, Kurume, Japan
| | - Kei-Ichiro Nakamura
- Division of Microscopic and Developmental Anatomy, Department of Anatomy, Kurume University School of Medicine, Kurume, Japan
| | - Makoto Takano
- Division of Integrated Autonomic Function, Department of Physiology, Kurume University School of Medicine, Kurume, Japan
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Role of PTHrP and Sensory Nerve Peptides in Regulating Contractility of Muscularis Mucosae and Detrusor Smooth Muscle in the Guinea Pig Bladder. J Urol 2016; 196:1287-94. [DOI: 10.1016/j.juro.2016.04.082] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/26/2016] [Indexed: 10/24/2022]
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Isogai A, Lee K, Mitsui R, Hashitani H. Functional coupling of TRPV4 channels and BK channels in regulating spontaneous contractions of the guinea pig urinary bladder. Pflugers Arch 2016; 468:1573-85. [DOI: 10.1007/s00424-016-1863-0] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2016] [Revised: 07/06/2016] [Accepted: 07/26/2016] [Indexed: 12/13/2022]
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Fry CH, Vahabi B. The Role of the Mucosa in Normal and Abnormal Bladder Function. Basic Clin Pharmacol Toxicol 2016; 119 Suppl 3:57-62. [PMID: 27228303 DOI: 10.1111/bcpt.12626] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2016] [Accepted: 05/23/2016] [Indexed: 12/20/2022]
Abstract
The internal face of the detrusor smooth muscle wall of the urinary bladder is covered by a mucosa, separating muscle from the hostile environment of urine. However, the mucosa is more than a very low permeability structure and offers a sensory function that monitors the extent of bladder filling and composition of the urine. The mucosa may be considered as a single functional structure and comprises a tight epithelial layer under which is a basement membrane and lamina propria. The latter region itself is a complex of afferent nerves, blood vessels, interstitial cells and in some species including human beings a muscularis mucosae. Stress on the bladder wall through physical or chemical stressors elicits release of chemicals, such as ATP, acetylcholine, prostaglandins and nitric oxide that modulate the activity of either afferent nerves or the muscular components of the bladder wall. The release and responses are graded so that the mucosa forms a dynamic sensory structure, and there is evidence that the gain of this system is increased in pathologies such as overactive bladder and bladder pain syndrome. This system therefore potentially provides a number of drug targets against these conditions, once a number of fundamental questions are answered. These include how is mediator release regulated; what are the intermediate roles of interstitial cells that surround afferent nerves and blood vessels; and what is the mode of communication between urothelium and muscle - by diffusion of mediators or by cell-to-cell communication?
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Affiliation(s)
- Christopher H Fry
- School of Physiology, Pharmacology & Neuroscience, University of Bristol, Bristol, UK.
| | - Bahareh Vahabi
- Department of Biological, Biomedical and Analytical Sciences, University of the West of England, Bristol, UK
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