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Takaoka EI, Kurobe M, Matsuoka K, Kamijo T, Kimura S, Watton PN, Robertson AM, Yoshimura N. Adenosine Receptor Mechanisms Underlying Bladder Dysfunction in Male Rats With Bladder Outlet Obstruction. Neurourol Urodyn 2025. [PMID: 40401426 DOI: 10.1002/nau.70080] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2024] [Revised: 03/21/2025] [Accepted: 05/04/2025] [Indexed: 05/23/2025]
Abstract
AIMS We examined the role of subtypes of adenosine receptors in bladder dysfunction and changes in the adenosine receptor expression in the bladder using male rats with partial bladder outlet obstruction (BOO). METHODS In Sprague-Dawley rats (male 8-weeks old), BOO was produced by a partial ligation of the urethra along a metal rod of a 1.2 mm outer diameter. Control rats underwent sham operation. Awake cystometrograms (CMG) were first recorded during saline instillation, and then an adenosine A1 receptor agonist (CCPA, 4.1 μM), an adenosine A2A antagonist (ZM241385, 15 μM), or inosine (1 mM) were applied intravesically in sham and BOO rats. In addition, mRNA levels of adenosine receptor subtypes in the bladder wall were measured using RT-PCR. Histological studies of bladder specimen were also performed. RESULTS Weights of BOO bladders were significantly (p < 0.0001) larger compared with sham bladders. In CMG, a number of non-voiding contractions (NVCs), bladder contraction amplitudes during voiding, bladder capacity, and post-void residual (PVR) were significantly (p < 0.001) increased compared with sham rats. Voiding efficiency (VE) was significantly (p < 0.001) reduced in BOO versus sham rats. Intravesical application of CCPA or inosine did not induce statistically significant effects on CMG parameters in BOO rats. Yet, ZM241385 induced a significant (p = 0.040) reduction in NVCs of BOO rats. mRNA levels of adenosine A2A and A3 receptors were significantly (p < 0.0001 and p = 0.0145, respectively) upregulated in the BOO bladder mucosa, whereas adenosine A2B receptors showed a significant (p < 0.0001) reduction in the BOO bladder mucosa compared with sham bladders. Histologically, we found the thickened detrusor muscle layer in BOO versus sham rats. CONCLUSIONS The male rat model of BOO seems to be suitable for exploring urethral obstruction-related bladder dysfunction at the compensated phase. In addition, the adenosine A2A receptor subtype would be a potential target for the treatment of male BOO patients with bladder overactivity. CLINICAL TRIAL REGISTRATION A clinical trial registration is not required as this study reported the basic research data using animal models.
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Affiliation(s)
- Ei-Ichiro Takaoka
- Department of Urology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
- Department of Urology, Jichi Medical University, Tochigi, Japan
| | - Masahiro Kurobe
- Department of Urology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Kanako Matsuoka
- Department of Urology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Tadanobu Kamijo
- Department of Urology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Shingo Kimura
- Department of Urology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Paul N Watton
- Department of Computer Science, Insigneo Institute for in silico Medicine, University of Sheffield, Sheffield, UK
| | - Anne M Robertson
- Department of Mechanical Engineering and Materials Science, University of Pittsburgh School of Engineering, Pittsburgh, Pennsylvania, USA
| | - Naoki Yoshimura
- Department of Urology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
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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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Michel MC, Cardozo L, Chermansky CJ, Cruz F, Igawa Y, Lee KS, Sahai A, Wein AJ, Andersson KE. Current and Emerging Pharmacological Targets and Treatments of Urinary Incontinence and Related Disorders. Pharmacol Rev 2023; 75:554-674. [PMID: 36918261 DOI: 10.1124/pharmrev.121.000523] [Citation(s) in RCA: 28] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2021] [Revised: 01/23/2023] [Accepted: 01/24/2023] [Indexed: 03/16/2023] Open
Abstract
Overactive bladder syndrome with and without urinary incontinence and related conditions, signs, and disorders such as detrusor overactivity, neurogenic lower urinary tract dysfunction, underactive bladder, stress urinary incontinence, and nocturia are common in the general population and have a major impact on the quality of life of the affected patients and their partners. Based on the deliberations of the subcommittee on pharmacological treatments of the 7th International Consultation on Incontinence, we present a comprehensive review of established drug targets in the treatment of overactive bladder syndrome and the aforementioned related conditions and the approved drugs used in its treatment. Investigational drug targets and compounds are also reviewed. We conclude that, despite a range of available medical treatment options, a considerable medical need continues to exist. This is largely because the existing treatments are symptomatic and have limited efficacy and/or tolerability, which leads to poor long-term adherence. SIGNIFICANCE STATEMENT: Urinary incontinence and related disorders are prevalent in the general population. While many treatments have been approved, few patients stay on long-term treatment despite none of them being curative. This paper provides a comprehensive discussion of existing and emerging treatment options for various types of incontinence and related disorders.
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Affiliation(s)
- Martin C Michel
- Department of Pharmacology, University Medical Center, Johannes Gutenberg University, Mainz, Germany (M.C.M.); Department of Urogynaecology, King's College Hospital, London, UK (L.C.); Department of Urology, Magee Women's Hospital, University of Pittsburgh, School of Medicine, Pittsburgh, Pennsylvania (C.J.C.); Department of Urology, Faculty of Medicine of University of Porto, Hospital São João and i3S Institute for Innovation and Investigation in Health, Porto, Portugal (F.C.); Department of Urology, Nagano Prefectural Shinshu Medical Center, Suzaka, Japan (Y.I.); Department of Urology Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea (K-S.L.); Guy's Hospital and King's College London, London, UK (A.S.); Dept. of Urology, Perlman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania (A.J.W.); Wake Forest Institute for Regenerative Medicine, Wake Forest University School of Medicine, Winston-Salem, North Carolina (A.J.W.); and Institute for Laboratory Medicine, Lund University, Lund, Sweden (K-E.A.)
| | - Linda Cardozo
- Department of Pharmacology, University Medical Center, Johannes Gutenberg University, Mainz, Germany (M.C.M.); Department of Urogynaecology, King's College Hospital, London, UK (L.C.); Department of Urology, Magee Women's Hospital, University of Pittsburgh, School of Medicine, Pittsburgh, Pennsylvania (C.J.C.); Department of Urology, Faculty of Medicine of University of Porto, Hospital São João and i3S Institute for Innovation and Investigation in Health, Porto, Portugal (F.C.); Department of Urology, Nagano Prefectural Shinshu Medical Center, Suzaka, Japan (Y.I.); Department of Urology Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea (K-S.L.); Guy's Hospital and King's College London, London, UK (A.S.); Dept. of Urology, Perlman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania (A.J.W.); Wake Forest Institute for Regenerative Medicine, Wake Forest University School of Medicine, Winston-Salem, North Carolina (A.J.W.); and Institute for Laboratory Medicine, Lund University, Lund, Sweden (K-E.A.)
| | - Christopher J Chermansky
- Department of Pharmacology, University Medical Center, Johannes Gutenberg University, Mainz, Germany (M.C.M.); Department of Urogynaecology, King's College Hospital, London, UK (L.C.); Department of Urology, Magee Women's Hospital, University of Pittsburgh, School of Medicine, Pittsburgh, Pennsylvania (C.J.C.); Department of Urology, Faculty of Medicine of University of Porto, Hospital São João and i3S Institute for Innovation and Investigation in Health, Porto, Portugal (F.C.); Department of Urology, Nagano Prefectural Shinshu Medical Center, Suzaka, Japan (Y.I.); Department of Urology Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea (K-S.L.); Guy's Hospital and King's College London, London, UK (A.S.); Dept. of Urology, Perlman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania (A.J.W.); Wake Forest Institute for Regenerative Medicine, Wake Forest University School of Medicine, Winston-Salem, North Carolina (A.J.W.); and Institute for Laboratory Medicine, Lund University, Lund, Sweden (K-E.A.)
| | - Francisco Cruz
- Department of Pharmacology, University Medical Center, Johannes Gutenberg University, Mainz, Germany (M.C.M.); Department of Urogynaecology, King's College Hospital, London, UK (L.C.); Department of Urology, Magee Women's Hospital, University of Pittsburgh, School of Medicine, Pittsburgh, Pennsylvania (C.J.C.); Department of Urology, Faculty of Medicine of University of Porto, Hospital São João and i3S Institute for Innovation and Investigation in Health, Porto, Portugal (F.C.); Department of Urology, Nagano Prefectural Shinshu Medical Center, Suzaka, Japan (Y.I.); Department of Urology Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea (K-S.L.); Guy's Hospital and King's College London, London, UK (A.S.); Dept. of Urology, Perlman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania (A.J.W.); Wake Forest Institute for Regenerative Medicine, Wake Forest University School of Medicine, Winston-Salem, North Carolina (A.J.W.); and Institute for Laboratory Medicine, Lund University, Lund, Sweden (K-E.A.)
| | - Yasuhiko Igawa
- Department of Pharmacology, University Medical Center, Johannes Gutenberg University, Mainz, Germany (M.C.M.); Department of Urogynaecology, King's College Hospital, London, UK (L.C.); Department of Urology, Magee Women's Hospital, University of Pittsburgh, School of Medicine, Pittsburgh, Pennsylvania (C.J.C.); Department of Urology, Faculty of Medicine of University of Porto, Hospital São João and i3S Institute for Innovation and Investigation in Health, Porto, Portugal (F.C.); Department of Urology, Nagano Prefectural Shinshu Medical Center, Suzaka, Japan (Y.I.); Department of Urology Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea (K-S.L.); Guy's Hospital and King's College London, London, UK (A.S.); Dept. of Urology, Perlman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania (A.J.W.); Wake Forest Institute for Regenerative Medicine, Wake Forest University School of Medicine, Winston-Salem, North Carolina (A.J.W.); and Institute for Laboratory Medicine, Lund University, Lund, Sweden (K-E.A.)
| | - Kyu-Sung Lee
- Department of Pharmacology, University Medical Center, Johannes Gutenberg University, Mainz, Germany (M.C.M.); Department of Urogynaecology, King's College Hospital, London, UK (L.C.); Department of Urology, Magee Women's Hospital, University of Pittsburgh, School of Medicine, Pittsburgh, Pennsylvania (C.J.C.); Department of Urology, Faculty of Medicine of University of Porto, Hospital São João and i3S Institute for Innovation and Investigation in Health, Porto, Portugal (F.C.); Department of Urology, Nagano Prefectural Shinshu Medical Center, Suzaka, Japan (Y.I.); Department of Urology Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea (K-S.L.); Guy's Hospital and King's College London, London, UK (A.S.); Dept. of Urology, Perlman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania (A.J.W.); Wake Forest Institute for Regenerative Medicine, Wake Forest University School of Medicine, Winston-Salem, North Carolina (A.J.W.); and Institute for Laboratory Medicine, Lund University, Lund, Sweden (K-E.A.)
| | - Arun Sahai
- Department of Pharmacology, University Medical Center, Johannes Gutenberg University, Mainz, Germany (M.C.M.); Department of Urogynaecology, King's College Hospital, London, UK (L.C.); Department of Urology, Magee Women's Hospital, University of Pittsburgh, School of Medicine, Pittsburgh, Pennsylvania (C.J.C.); Department of Urology, Faculty of Medicine of University of Porto, Hospital São João and i3S Institute for Innovation and Investigation in Health, Porto, Portugal (F.C.); Department of Urology, Nagano Prefectural Shinshu Medical Center, Suzaka, Japan (Y.I.); Department of Urology Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea (K-S.L.); Guy's Hospital and King's College London, London, UK (A.S.); Dept. of Urology, Perlman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania (A.J.W.); Wake Forest Institute for Regenerative Medicine, Wake Forest University School of Medicine, Winston-Salem, North Carolina (A.J.W.); and Institute for Laboratory Medicine, Lund University, Lund, Sweden (K-E.A.)
| | - Alan J Wein
- Department of Pharmacology, University Medical Center, Johannes Gutenberg University, Mainz, Germany (M.C.M.); Department of Urogynaecology, King's College Hospital, London, UK (L.C.); Department of Urology, Magee Women's Hospital, University of Pittsburgh, School of Medicine, Pittsburgh, Pennsylvania (C.J.C.); Department of Urology, Faculty of Medicine of University of Porto, Hospital São João and i3S Institute for Innovation and Investigation in Health, Porto, Portugal (F.C.); Department of Urology, Nagano Prefectural Shinshu Medical Center, Suzaka, Japan (Y.I.); Department of Urology Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea (K-S.L.); Guy's Hospital and King's College London, London, UK (A.S.); Dept. of Urology, Perlman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania (A.J.W.); Wake Forest Institute for Regenerative Medicine, Wake Forest University School of Medicine, Winston-Salem, North Carolina (A.J.W.); and Institute for Laboratory Medicine, Lund University, Lund, Sweden (K-E.A.)
| | - Karl-Erik Andersson
- Department of Pharmacology, University Medical Center, Johannes Gutenberg University, Mainz, Germany (M.C.M.); Department of Urogynaecology, King's College Hospital, London, UK (L.C.); Department of Urology, Magee Women's Hospital, University of Pittsburgh, School of Medicine, Pittsburgh, Pennsylvania (C.J.C.); Department of Urology, Faculty of Medicine of University of Porto, Hospital São João and i3S Institute for Innovation and Investigation in Health, Porto, Portugal (F.C.); Department of Urology, Nagano Prefectural Shinshu Medical Center, Suzaka, Japan (Y.I.); Department of Urology Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea (K-S.L.); Guy's Hospital and King's College London, London, UK (A.S.); Dept. of Urology, Perlman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania (A.J.W.); Wake Forest Institute for Regenerative Medicine, Wake Forest University School of Medicine, Winston-Salem, North Carolina (A.J.W.); and Institute for Laboratory Medicine, Lund University, Lund, Sweden (K-E.A.)
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Lee WC, Yu HR, Tain YL, Wu KL, Chuang YC, Chan JY. Vinpocetine Ameliorates Metabolic-Syndrome-Associated Bladder Overactivity in Fructose-Fed Rats by Restoring Succinate-Modulated cAMP Levels and Exerting Anti-Inflammatory Effects in the Bladder Detrusor Muscle. Biomedicines 2022; 10:2716. [PMID: 36359236 PMCID: PMC9687486 DOI: 10.3390/biomedicines10112716] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2022] [Revised: 10/21/2022] [Accepted: 10/24/2022] [Indexed: 11/03/2023] Open
Abstract
Succinate and its receptor, the G protein-coupled receptor 91 (GPR91), have pathological implications in metabolic syndrome (MetS) and its associated bladder dysfunction, particularly in decreasing bladder cAMP levels and promoting proinflammation. Using fructose-fed rats (FFRs), a rat model of MetS, we investigate the effects of vinpocetine (a phosphodiesterase-1 inhibitor) and celecoxib (a selective cyclooxygenase-2 inhibitor) on MetS-associated bladder overactivity. Phenotypes of the overactive bladder, including increased micturition frequency and a shortened intercontractile interval in cystometry, were observed in FFRs, together with elevated succinate levels in the liver and serum and the downregulation of GPR91 in the liver and urinary bladder. Treatments with vinpocetine and celecoxib improved tissue fibrosis and ameliorated the overexpression of the inflammatory cytokines, such as IL-1β, in the liver and bladder. In bladder organ bath studies, vinpocetine, but not celecoxib, treatment restored the contraction and relaxation responses of the detrusor muscle strip in response to KCl, carbachol, and forskolin stimulation. At a molecular level, vinpocetine and celecoxib treatments modulated the downstream messengers of GPR91 (i.e., ERK1/2 and JNK), suppressed NF-κB and IL-1β expressions in the bladder, and prevented the fibrogenesis observed in FFRs. The exogenous application of succinate to a bladder organ bath significantly reduced the forskolin-induced cAMP production by the detrusor muscle, which was notably restored in the presence of vinpocetine. Together, these results suggest that vinpocetine may alleviate the MetS-associated bladder overactivity by restoring the succinate-modulated detrusor cAMP production and exerting the anti-inflammatory effects in the bladder detrusor muscle.
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Affiliation(s)
- Wei-Chia Lee
- Division of Urology, Kaohsiung Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Kaohsiung 833, Taiwan
| | - Hong-Ren Yu
- Department of Paediatrics, Kaohsiung Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Kaohsiung 833, Taiwan
| | - You-Lin Tain
- Department of Paediatrics, Kaohsiung Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Kaohsiung 833, Taiwan
| | - Kay L.H. Wu
- Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung 833, Taiwan
| | - Yao-Chi Chuang
- Division of Urology, Kaohsiung Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Kaohsiung 833, Taiwan
| | - Julie Y.H. Chan
- Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung 833, Taiwan
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Cheng F, Watton PN, Pederzani G, Kurobe M, Takaoka EI, Chapple C, Birder L, Yoshimura N, Robertson AM. A constrained mixture-micturition-growth (CMMG) model of the urinary bladder: Application to partial bladder outlet obstruction (BOO). J Mech Behav Biomed Mater 2022; 134:105337. [PMID: 35863296 PMCID: PMC9835014 DOI: 10.1016/j.jmbbm.2022.105337] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Revised: 04/13/2022] [Accepted: 06/24/2022] [Indexed: 01/14/2023]
Abstract
We present a constrained mixture-micturition-growth (CMMG) model for the bladder. It simulates bladder mechanics, voiding function (micturition) and tissue adaptations in response to altered biomechanical conditions. The CMMG model is calibrated with both in vivo and in vitro data from healthy male rat urinary bladders (cystometry, bioimaging of wall structure, mechanical testing) and applied to simulate the growth and remodeling (G&R) response to partial bladder outlet obstruction (BOO). The bladder wall is represented as a multi-layered, anisotropic, nonlinear constrained mixture. A short time scale micturition component of the CMMG model accounts for the active and passive mechanics of voiding. Over a second, longer time scale, G&R algorithms for the evolution of both cellular and extracellular constituents act to maintain/restore bladder (homeostatic) functionality. The CMMG model is applied to a spherical membrane model of the BOO bladder utilizing temporal data from an experimental male rodent model to parameterize and then verify the model. Consistent with the experimental studies of BOO, the model predicts: an initial loss of voiding capacity followed by hypertrophy of SMC to restore voiding function; bladder enlargement; collagen remodeling to maintain its role as a protective sheath; and increased voiding duration with lower average flow rate. This CMMG model enables a mechanistic approach for investigating the bladder's structure-function relationship and its adaption in pathological conditions. While the approach is illustrated with a conceptual spherical bladder model, it provides the basis for application of the CMMG model to anatomical geometries. Such a mechanistic approach has promise as an in silico tool for the rational development of new surgical and pharmacological treatments for bladder diseases such as BOO.
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Affiliation(s)
- Fangzhou Cheng
- Department of Mechanical Engineering and Materials Science, University of Pittsburgh, Pittsburgh, United States
| | - Paul N Watton
- Department of Mechanical Engineering and Materials Science, University of Pittsburgh, Pittsburgh, United States; Department of Computer Science & Insigneo Institute for in silico Medicine, University of Sheffield, Sheffield, United Kingdom.
| | - Giulia Pederzani
- Department of Computer Science & Insigneo Institute for in silico Medicine, University of Sheffield, Sheffield, United Kingdom
| | - Masahiro Kurobe
- Department of Urology, University of Pittsburgh, Pittsburgh, United States
| | - Ei-Ichiro Takaoka
- Department of Urology, University of Pittsburgh, Pittsburgh, United States
| | - Chris Chapple
- Sheffield Teaching Hospitals NHS Foundation Trust, Sheffield, United Kingdom
| | - Lori Birder
- Sheffield Teaching Hospitals NHS Foundation Trust, Sheffield, United Kingdom; Department of Medicine, University of Pittsburgh, United States
| | - Naoki Yoshimura
- Department of Urology, University of Pittsburgh, Pittsburgh, United States
| | - Anne M Robertson
- Department of Mechanical Engineering and Materials Science, University of Pittsburgh, Pittsburgh, United States
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Chen L, Lv L, Zhang L, Gao Z, Liu Y, Wang S, Zhou N, Xia Y, Cui J, Jiang X, Zhang X, Li Y, Shi B. Metformin ameliorates bladder dysfunction in a rat model of partial bladder outlet obstruction. Am J Physiol Renal Physiol 2021; 320:F838-F858. [PMID: 33645317 DOI: 10.1152/ajprenal.00625.2020] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2020] [Accepted: 02/23/2021] [Indexed: 12/12/2022] Open
Abstract
Alteration of bladder morphology and function was the most important consequence of bladder outlet obstruction (BOO). Using a rat model of partial BOO (pBOO), we found that rats treated with metformin showed lower baseline pressures with a reduced inflammatory reaction in the early phase (2 wk) after pBOO. The NLR family pyrin domain containing 3 inflammasome pathway was inhibited in pBOO rat bladders with treatment of metformin in the early phase. Metformin reduced the activity of NLR family pyrin domain containing 3 in primary urothelial cells. In the chronic phase (9 wk after pBOO), metformin treatment ameliorated bladder fibrosis and improved the reduced compliance. Treatment with metformin suppressed the activation of Smad3 and compensated the diminished autophagy in 9-wk pBOO rat bladders. Autophagy was inhibited with upregulation of profibrotic proteins in primary fibroblasts from chronic pBOO bladders, which could be restored by administration of metformin. The antifibrotic effects of metformin on fibroblasts were diminished after silencing of AMP-activated protein kinase or light chain 3B. In summary, this study elucidates that oral administration of metformin relieves inflammation in the bladder during the early phase of pBOO. Long-term oral administration of metformin can prevent functional and histological changes in the pBOO rat bladder. The current study suggests that metformin might be used to prevent the development of bladder dysfunction secondary to BOO.NEW & NOTEWORTHY The present study in a rat model showed that oral administration of metformin alleviated inflammation following partial bladder outlet obstruction in the early phase and ameliorated bladder fibrosis as well as bladder dysfunction by long-term treatment. Our study indicated that metformin is a potential drug to inhibit bladder remodeling and alleviate bladder dysfunction. Clinical trials are needed to validate the effect of metformin on the bladder dysfunction and bladder fibrosis in the future.
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Affiliation(s)
- Lipeng Chen
- Department of Urology, Qilu Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China
- Key Laboratory of Urinary Precision Diagnosis and Treatment in Universities of Shandong, Jinan, China
| | - Linchen Lv
- Department of Urology, Qilu Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China
- Key Laboratory of Urinary Precision Diagnosis and Treatment in Universities of Shandong, Jinan, China
| | - Lekai Zhang
- Department of Urology, Qilu Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China
- Key Laboratory of Urinary Precision Diagnosis and Treatment in Universities of Shandong, Jinan, China
| | - Zhengdong Gao
- Department of Urology, Qilu Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China
- Key Laboratory of Urinary Precision Diagnosis and Treatment in Universities of Shandong, Jinan, China
| | - Yaxiao Liu
- Department of Urology, Qilu Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China
- Key Laboratory of Urinary Precision Diagnosis and Treatment in Universities of Shandong, Jinan, China
- Laboratory of Basic Medical Sciences, Qilu Hospital, Cheeloo College of Medicine, Jinan, China
| | - Shuai Wang
- Department of Urology, Qilu Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China
- Key Laboratory of Urinary Precision Diagnosis and Treatment in Universities of Shandong, Jinan, China
| | - Nan Zhou
- Department of Urology, Qilu Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China
- Key Laboratory of Urinary Precision Diagnosis and Treatment in Universities of Shandong, Jinan, China
| | - Yangyang Xia
- Department of Urology, Qilu Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China
- Key Laboratory of Urinary Precision Diagnosis and Treatment in Universities of Shandong, Jinan, China
| | - Jianfeng Cui
- Department of Urology, Qilu Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China
- Key Laboratory of Urinary Precision Diagnosis and Treatment in Universities of Shandong, Jinan, China
| | - Xuewen Jiang
- Department of Urology, Qilu Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China
- Key Laboratory of Urinary Precision Diagnosis and Treatment in Universities of Shandong, Jinan, China
| | - Xiulin Zhang
- Department of Urology, Second Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Yan Li
- Department of Urology, Qilu Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China
- Key Laboratory of Urinary Precision Diagnosis and Treatment in Universities of Shandong, Jinan, China
| | - Benkang Shi
- Department of Urology, Qilu Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China
- Key Laboratory of Urinary Precision Diagnosis and Treatment in Universities of Shandong, Jinan, China
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7
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He W, Xiang H, Liu D, Liu J, Li M, Wang Q, Qian Q, Li Y, Fu X, Chen P, Guo Y, Zeng G, Wu Z, Zhan D, Wang X, DiSanto ME, Zhang X. Changes in the expression and function of the PDE5 pathway in the obstructed urinary bladder. J Cell Mol Med 2020; 24:13181-13195. [PMID: 33009887 PMCID: PMC7701571 DOI: 10.1111/jcmm.15926] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Revised: 09/04/2020] [Accepted: 09/08/2020] [Indexed: 02/06/2023] Open
Abstract
Our study aims to explore changes in bladder contractility and the phosphodiesterase type 5 (PDE5) signalling pathway in response to partial bladder outlet obstruction (PBOO). A surgically induced male rat PBOO model and human obstructed bladder tissues were used. Histological changes were examined by H&E and Masson's trichrome staining. Bladder strip contractility was measured via organ bath. The expressions of nitric oxide synthase (NOS) isoforms, PDE5, muscarinic cholinergic receptor (CHRM) isoforms and PDE4 isoforms in bladder were detected by RT‐PCR and Western blotting. The immunolocalization of the PDE5 protein and its functional activity were also determined. PBOO bladder tissue exhibited significant SM hypertrophy and elevated responsiveness to KCl depolarization and the muscarinic receptor agonist carbachol. NOS isoforms, PDE5, CHRM2, CHRM3 and PDE4A were up‐regulated in obstructed bladder tissue, whereas no change in PDE4B and PDE4D isoform expression was observed. With regard to PDE5, it was expressed in the SM bundles of bladder. Interestingly, obstructed bladder exhibited less relaxation responsiveness to sodium nitroprusside (SNP), but an exaggerated PDE5 inhibition effect. The up‐regulation of PDE5 could contribute to the lack of effect on Qmax for benign prostatic hyperplasia/lower urinary tract symptom (BPH/LUTS) patients treated with PDE5 inhibitors. Moreover, PDE5 (with presence of NO) and PDE4 may serve as new therapeutic targets for bladder diseases such as BPH‐induced LUTS and overactive bladder (OAB).
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Affiliation(s)
- Weixiang He
- Department of Urology, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Han Xiang
- Department of Urology, The Second Affiliated Hospital of Soochow University, Suzhou, China
| | - Daoquan Liu
- Department of Urology, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Jianmin Liu
- Department of Urology, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Mingzhou Li
- Department of Urology, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Qian Wang
- Department of Urology, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Qiaofeng Qian
- Department of Urology, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Yan Li
- Department of Urology, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Xun Fu
- Department of Urology, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Ping Chen
- Department of Urology, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Yuming Guo
- Department of Urology, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Guang Zeng
- Department of Urology, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Zhonghua Wu
- Department of Urology, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Daxing Zhan
- Department of Anesthesiology, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Xinghuan Wang
- Department of Urology, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Michael E DiSanto
- Department of Surgery and Biomedical Sciences, Cooper Medical School of Rowan University, Camden, NJ, USA
| | - Xinhua Zhang
- Department of Urology, Zhongnan Hospital of Wuhan University, Wuhan, China
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8
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Sekido N, Otsuki T, Kida J, Mashimo H, Wakamatsu D, Okada H, Matsuya H. EP2 and EP3 receptors as therapeutic targets for underactive bladder/detrusor underactivity due to diabetic cystopathy in a type 1 diabetic rat model. Low Urin Tract Symptoms 2020; 12:285-291. [PMID: 32410343 DOI: 10.1111/luts.12317] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Revised: 04/09/2020] [Accepted: 04/19/2020] [Indexed: 12/14/2022]
Abstract
OBJECTIVES Diabetic cystopathy (DC) is recognized as one of the major etiologies of underactive bladder (UAB)/detrusor underactivity (DU). Although DC was first reported about three decades ago, there is a distinct lack of effective pharmacological management methods for UAB/DU due to DC with a robust certainty of evidence. In this study, we investigated whether EP2 and EP3 receptors are promising targets of pharmacological management of UAB/DU due to DC. METHODS We used streptozotocin (STZ)-induced diabetic Sprague-Dawley rats with postvoid residual urine (PVR) greater than 0.1 mL. Sixteen weeks after induction of diabetes, we performed awake single cystometry after oral administration of the vehicle, an α-blocker (tamsulosin [TAM], 0.1 and 0.3 mg/kg), a cholinesterase inhibitor (distigmine [DIS], 0.3 and 1.0 mg/kg), or an EP2/3 dual agonist (ONO-8055, 0.01 and 0.03 mg/kg). We compared cystometric parameters after administration of the vehicle and drugs using a paired t test. P < .05 was considered to be statistically significant. RESULTS Compared with the vehicle, TAM significantly decreased maximum intravesical pressure during voiding (Pmax), while DIS significantly increased it. However, neither drug significantly affected PVR or the residual urine rate (RUR). On the other hand, ONO-8055 significantly decreased PVR and tended to decrease RUR, although it did not significantly affect Pmax. CONCLUSION The present study was unable to demonstrate that stimulation of EP2 and EP3 receptors caused major improvements in UAB/DU due to DC. However, this equivocal result could arise from inherent limitations of the STZ-induced diabetic rat as a UAB/DU model.
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Affiliation(s)
- Noritoshi Sekido
- Department of Urology, School of Medicine, Faculty of Medicine, Toho University Medical Center Ohashi Hospital, Tokyo, Japan
| | - Takeya Otsuki
- Discovery Research Laboratories, Ono Pharmaceutical Co, Ltd, Osaka, Japan
| | - Jun Kida
- Discovery Research Laboratories, Ono Pharmaceutical Co, Ltd, Osaka, Japan
| | - Hiroko Mashimo
- Discovery Research Laboratories, Ono Pharmaceutical Co, Ltd, Osaka, Japan
| | - Daisuke Wakamatsu
- Discovery Research Laboratories, Ono Pharmaceutical Co, Ltd, Osaka, Japan
| | - Hiroki Okada
- Discovery Research Laboratories, Ono Pharmaceutical Co, Ltd, Osaka, Japan
| | - Hidekazu Matsuya
- Discovery Research Laboratories, Ono Pharmaceutical Co, Ltd, Osaka, Japan
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9
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Choi JB, Jeon SH, Kwon EB, Bae WJ, Cho HJ, Ha US, Hong SH, Lee JY, Kim SW. The effects of oral administration of the novel muscarinic receptor antagonist DA-8010 on overactive bladder in rat with bladder outlet obstruction. BMC Urol 2020; 20:41. [PMID: 32303205 PMCID: PMC7164290 DOI: 10.1186/s12894-020-00611-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Accepted: 04/07/2020] [Indexed: 02/05/2023] Open
Abstract
Background DA-8010 is a novel compound developed for the treatment of overactive bladder (OAB) and urinary incontinence. The aims of this study were to investigate the effects of DA-8010 on OAB in a rat model. Methods Study animals were divided into the following five groups of seven animals each: a sham-operated control group, a control group with partial bladder outlet obstruction (BOO) (OAB group), and three DA-8010 (doses of 0.3 mg/kg/day, 1 mg/kg/day, and 3 mg/kg/day, respectively) with partial BOO groups. Oral administration of the drugs was continued for 14 days after 2 weeks of partial BOO. After 4 weeks of partial BOO, cystometrography was performed in all groups. Additionally, pro-inflammatory cytokines, Rho-kinases, and histology of the bladder were analyzed. Results There was a significant increase in the contraction interval and a decrease in contraction pressure in the 3 mg/kg/day DA-8010 group versus those in the OAB group. Rho kinase was also significantly decreased in the DA-8010 3 mg/kg/day dosage treatment group. The increased ratio of collagen to smooth muscle after partial BOO was significantly attenuated in the DA-8010 3 mg/kg/day dosage group. Conclusions Oral administration of DA-8010 at 3 mg/kg/day improved findings in an OAB rat model induced by partial BOO. Our results suggest that the novel muscarinic receptor antagonist DA-8010 may be a promising drug for treating patients with OAB.
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Affiliation(s)
- Jin Bong Choi
- Department of Urology, Bucheon St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Seung Hwan Jeon
- Department of Urology, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Eun Bi Kwon
- Korea Bio Medical Science Institute, Seoul, Republic of Korea
| | - Woong Jin Bae
- Department of Urology, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea and Catholic Integrative Medicine Research Institute, The Catholic University of Korea, Banpo-daero 222, Seocho-gu, Seoul, 06591, Seoul, Republic of Korea
| | - Hyuk Jin Cho
- Department of Urology, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - U-Syn Ha
- Department of Urology, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Sung-Hoo Hong
- Department of Urology, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Ji Youl Lee
- Department of Urology, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Sae Woong Kim
- Department of Urology, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea and Catholic Integrative Medicine Research Institute, The Catholic University of Korea, Banpo-daero 222, Seocho-gu, Seoul, 06591, Seoul, Republic of Korea.
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10
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Combination phosphodiesterase type 4 inhibitor and phosphodiesterase type 5 inhibitor treatment reduces non-voiding contraction in a rat model of overactive bladder. PLoS One 2019; 14:e0220788. [PMID: 31461445 PMCID: PMC6713339 DOI: 10.1371/journal.pone.0220788] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Accepted: 07/23/2019] [Indexed: 01/24/2023] Open
Abstract
Introduction Current treatments for overactive bladder (OAB) are often discontinued due to side effects or lack of efficacy. The goal of this study was to determine if combining a phosphodiesterase type 4 inhibitor (PDE4i); with a type 5 inhibitor (PDE5i); would have a beneficial effect on OAB symptoms and if a reduced dose of PDE4i in combination with PDE5i could also provide a beneficial effect in OAB. We hypothesized that PDE5i and PDE4i combination treatment could be utilized to reduce non-voiding contractions and smooth muscle disruption in a rat model of OAB. Methods Fifty-eight age-matched Sprague-Dawley rats underwent PBOO and daily gavage with PDE4i alone (roflumilast; 1mg/kg), PDE5i alone (tadalafil;10mg/kg), high dose combination (PDE4i 1mg/kg, PDE5i 10mg/kg), low dose combination (PDE4i 0.2mg/kg, PDE5i 10mg/kg), or vehicle for 28 days. Fourteen animals underwent sham PBOO with vehicle. Rats underwent conscious and anesthetized cystometry 28 days after PBOO and were euthanized for qualitative bladder histology. One-way ANOVA on ranks with a Dunn’s post hoc test was used to indicate statistically significant differences between groups (p<0.05). Results Bladder & urethral weight was significantly increased after PBOO with vehicle, PDE4i alone, and PDE5i alone, but not with either combination treatment. Frequency of non-voiding contractions during both conscious and anesthetized cystometry increased significantly after PBOO with vehicle, but not after PDE4i or high dose combination treatments compared to sham PBOO. Threshold pressure for voiding was significantly decreased with high dose combination compared to vehicle. PBOO treated with PDE4i alone or high dose combination showed less bladder smooth muscle fibrosis than vehicle, PDE5i alone, or low dose combination treatments. Conclusion A PDE4i and PDE5i combination treatment has potential benefit in reducing OAB symptoms, but future research is needed.
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11
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Linhares BL, Nascimento NRF, Gonzaga-Silva LF, Santos CF, Moraes MO, Marinho LB, Silva APG, Fonteles MC, Reges R. Effect of co-administration of two different phosphodiesterase inhibitors and a β3-adrenoceptor agonist in an experimental model of detrusor overactivity. Eur J Pharmacol 2018; 833:425-431. [DOI: 10.1016/j.ejphar.2018.06.018] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2018] [Revised: 06/13/2018] [Accepted: 06/15/2018] [Indexed: 02/07/2023]
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12
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Phosphodiesterase type 4 inhibition enhances nitric oxide- and hydrogen sulfide-mediated bladder neck inhibitory neurotransmission. Sci Rep 2018; 8:4711. [PMID: 29549279 PMCID: PMC5856743 DOI: 10.1038/s41598-018-22934-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Accepted: 03/02/2018] [Indexed: 01/01/2023] Open
Abstract
Nitric oxide (NO) and hydrogen sulfide (H2S) play a pivotal role in nerve-mediated relaxation of the bladder outflow region. In the bladder neck, a marked phosphodiesterase type 4 (PDE4) expression has also been described and PDE4 inhibitors, as rolipram, produce smooth muscle relaxation. This study investigates the role of PDE4 isoenzyme in bladder neck gaseous inhibitory neurotransmission. We used Western blot and double immunohistochemical staining for the detection of NPP4 (PDE4) and PDE4A and organ baths for isometric force recording to roflumilast and tadalafil, PDE4 and PDE5, respectively, inhibitors in pig and human samples. Endogenous H2S production measurement and electrical field stimulation (EFS) were also performed. A rich PDE4 and PDE4A expression was observed mainly limited to nerve fibers of the smooth muscle layer of both species. Moreover, roflumilast produced a much more potent smooth muscle relaxation than that induced by tadalafil. In porcine samples, H2S generation was diminished by H2S and NO synthase inhibition and augmented by roflumilast. Relaxations elicited by EFS were potentiated by roflumilast. These results suggest that PDE4, mainly PDE4A, is mostly located within nerve fibers of the pig and human bladder neck, where roflumilast produces a powerful smooth muscle relaxation. In pig, the fact that roflumilast increases endogenous H2S production and EFS-induced relaxations suggests a modulation of PDE4 on NO- and H2S-mediated inhibitory neurotransmission.
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13
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Kim SJ, Jeon SH, Kwon EB, Jeong HC, Choi SW, Bae WJ, Cho HJ, Ha US, Hong SH, Lee JY, Hwang SY, Kim SW. Improvement of Persistent Detrusor Overactivity through Treatment with a Phytotherapeutic Agent (WSY-1075) after Relief of Bladder Outlet Obstruction. World J Mens Health 2017; 36:153-160. [PMID: 29076300 PMCID: PMC5924957 DOI: 10.5534/wjmh.17010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2017] [Revised: 08/07/2017] [Accepted: 08/18/2017] [Indexed: 01/02/2023] Open
Abstract
Purpose Many patients with benign prostatic hyperplasia need treatment for remaining storage symptoms after surgery. Therefore, we evaluated the effect of the phytotherapeutic agent WSY-1075 on persistent detrusor overactivity (DO) after the relief of bladder outlet obstruction (BOO). Materials and Methods Rats were assigned to 3 groups: control (n=6), persistent DO (n=6), and persistent DO treated with the phytotherapeutic agent WSY-1075 (n=6). Persistent DO after relief of partial BOO was generated in the rat model, and 6 of the rats with this condition were orally administered WSY-1075. After 4 weeks of administration, cystometry was performed. Additionally, 8-hydroxy-2-deoxyguanosine and superoxide dismutase were measured to evaluate oxidative stress in the bladder. Pro-inflammatory cytokines, such as interleukin-8 and tumor necrosis factor-α, were analyzed, as were the M2 and M3 muscarinic receptors of the bladder. Results Significantly increased contraction pressure and a decreased contraction interval were observed in the persistent DO group after relief of BOO. Moreover, oxidative stress, pro-inflammatory cytokines, and M3 muscarinic receptors were significantly increased. After treatment with WSY-1075, significantly reduced DO was observed by cystometry in comparison with the persistent DO group. Additionally, significantly decreased levels of oxidative stress, pro-inflammatory cytokines, and M3 muscarinic receptors in the bladder were observed after treatment with WSY-1075. Conclusions Treatment with WSY-1075 improved persistent DO after the relief of BOO mediated by antioxidative and anti-inflammatory effects. Further studies are necessary to identify the exact mechanism of the treatment effect of WSY-1075.
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Affiliation(s)
- Su Jin Kim
- Department of Urology, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea
| | - Seung Hwan Jeon
- Department of Urology, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea
| | - Eun Bi Kwon
- Department of Urology, Institute of Biomedical Industry, The Catholic University of Korea, Seoul, Korea.,Korea Biomedical Science Institute, Seoul, Korea
| | - Hyun Cheol Jeong
- Department of Urology, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea
| | - Sae Woong Choi
- Department of Urology, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea
| | - Woong Jin Bae
- Department of Urology, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea.,Catholic Integrative Medicine Research Institute, College of Medicine, The Catholic University of Korea, Seoul, Korea
| | - Hyuk Jin Cho
- Department of Urology, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea
| | - U Syn Ha
- Department of Urology, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea
| | - Sung Hoo Hong
- Department of Urology, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea
| | - Ji Youl Lee
- Department of Urology, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea
| | | | - Sae Woong Kim
- Department of Urology, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea.,Catholic Integrative Medicine Research Institute, College of Medicine, The Catholic University of Korea, Seoul, Korea.
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Michishita M, Yano K, Tomita KI, Yoshikawa S, Matsuzaki O, Kasahara KI. Decreased Monoamine Oxidase A Expression and Activity in the Bladders of Rats With Partial Outlet Obstruction. Urology 2017; 110:263.e9-263.e13. [PMID: 28916252 DOI: 10.1016/j.urology.2017.08.048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Revised: 07/10/2017] [Accepted: 08/31/2017] [Indexed: 11/18/2022]
Abstract
OBJECTIVE To investigate changes in expression and activity of monoamine oxidase A (MAO-A) in rats with partial bladder outlet obstruction (pBOO). Previous studies suggested that monoamines, such as serotonin (5-hydroxytryptamine [5-HT]) and noradrenaline, are involved in bladder hyperactivity secondary to pBOO. However, little is known about the role of MAO-A, an enzyme oxidizing 5-hydroxytryptamine and noradrenalin, in the pathogenesis. MATERIALS AND METHODS Female Sprague Dawley rats were subjected to sham or pBOO operations for 7 days, then their bladders were isolated. MAO-A protein levels in the bladder were examined by Western blotting. MAO-A activity was measured by the commercially available MAO-Glo Assay kit. In addition, MAO-A distribution in the bladder was examined by immunohistochemistry. RESULTS Weights of the bladders from rats with pBOO were increased about 3.5-fold, compared with those from sham rats. Significant decreases in MAO-A protein and activity levels were observed in whole bladder of rats with pBOO compared with those of sham rats. By immunohistochemistry, it was firstly demonstrated that MAO-A was predominantly expressed in the detrusor layer of the sham rat bladders. The intensity of staining was decreased after pBOO operation. CONCLUSION We demonstrated, for the first time, the distribution of MAO-A in the bladder and the pathologic changes in MAO-A protein and activity levels in rats with pBOO. This marked decrease in MAO-A potentially resulting in increased monoamine levels, especially in the detrusor of rat bladder, might be a key factor explaining the mechanism of bladder overactivity associated with pBOO.
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Affiliation(s)
- Mai Michishita
- Laboratory for Pharmacology, Pharmaceuticals Research Center, Asahi Kasei Pharma Corporation, Izunokuni, Shizuoka, Japan.
| | - Kazuo Yano
- Laboratory for Pharmacology, Pharmaceuticals Research Center, Asahi Kasei Pharma Corporation, Izunokuni, Shizuoka, Japan
| | - Ken-Ichi Tomita
- Laboratory for Pharmacology, Pharmaceuticals Research Center, Asahi Kasei Pharma Corporation, Izunokuni, Shizuoka, Japan
| | - Satoru Yoshikawa
- Laboratory for Pharmacology, Pharmaceuticals Research Center, Asahi Kasei Pharma Corporation, Izunokuni, Shizuoka, Japan
| | - Osamu Matsuzaki
- Laboratory for Pharmacology, Pharmaceuticals Research Center, Asahi Kasei Pharma Corporation, Izunokuni, Shizuoka, Japan
| | - Ken-Ichi Kasahara
- Laboratory for Pharmacology, Pharmaceuticals Research Center, Asahi Kasei Pharma Corporation, Izunokuni, Shizuoka, Japan
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15
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Michishita M, Yano K, Tomita KI, Matsuzaki O, Kasahara KI. Piezo1 expression increases in rat bladder after partial bladder outlet obstruction. Life Sci 2016; 166:1-7. [PMID: 27756599 DOI: 10.1016/j.lfs.2016.10.017] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2016] [Revised: 10/09/2016] [Accepted: 10/14/2016] [Indexed: 12/11/2022]
Abstract
AIMS For patients with benign prostatic hyperplasia (BPH), storage symptoms due to bladder dysfunction are bothersome, and that mechanism elucidation is needed. Piezo1, a mechanically activated ion channel, is believed to play a role in sensing bladder distension. To investigate the involvement of Piezo1 in bladder dysfunction, we examined the expression and distribution of Piezo1 and neurofilament (NF-L) to understand pathological alterations in rat bladders with partial bladder outlet obstruction (pBOO), an animal model of BPH. MAIN METHODS Female Sprague-Dawley rats were subjected to sham or pBOO operations. On days 3, 7, and 14 after pBOO, Piezo1 mRNA levels in the bladder were examined by quantitative real-time PCR. The expression of light NF-L was also examined by western blotting. On day 7, the distributions of Piezo1 were examined by in situ hybridization. KEY FINDINGS The expression levels of Piezo1 mRNA in whole bladder were significantly increased from days 3 to 14 after pBOO. On day 7 in pBOO rats, significant increases in Piezo1 mRNA were observed in the detrusor layer as well as the suburothelial layer, while the predominant distribution was observed in the urothelium of sham rats. Coinciding with the increase in Piezo1, the decreases in NF-L expression were observed in the bladder from pBOO rats. SIGNIFICANCE The increase in Piezo1 in pBOO rat bladders might be involved in the compensatory mechanism associated with bladder denervation including the decrease in NF-L. Inhibition of Piezo-1 may be a new therapeutic approach to ameliorate the storage dysfunction shown in pBOO.
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Affiliation(s)
- Mai Michishita
- Laboratory for Pharmacology, Pharmaceuticals Research Center, Asahi Kasei Pharma Corporation, 632-1 Mifuku, Izunokuni, Shizuoka 410-2321, Japan.
| | - Kazuo Yano
- Laboratory for Pharmacology, Pharmaceuticals Research Center, Asahi Kasei Pharma Corporation, 632-1 Mifuku, Izunokuni, Shizuoka 410-2321, Japan
| | - Ken-Ichi Tomita
- Laboratory for Pharmacology, Pharmaceuticals Research Center, Asahi Kasei Pharma Corporation, 632-1 Mifuku, Izunokuni, Shizuoka 410-2321, Japan
| | - Osamu Matsuzaki
- Laboratory for Pharmacology, Pharmaceuticals Research Center, Asahi Kasei Pharma Corporation, 632-1 Mifuku, Izunokuni, Shizuoka 410-2321, Japan
| | - Ken-Ichi Kasahara
- Laboratory for Pharmacology, Pharmaceuticals Research Center, Asahi Kasei Pharma Corporation, 632-1 Mifuku, Izunokuni, Shizuoka 410-2321, Japan
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16
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Promising Effects of a Novel EP2 and EP3 Receptor Dual Agonist, ONO-8055, on Neurogenic Underactive Bladder in a Rat Lumbar Canal Stenosis Model. J Urol 2016; 196:609-16. [PMID: 26880410 DOI: 10.1016/j.juro.2016.02.064] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/06/2016] [Indexed: 12/29/2022]
Abstract
PURPOSE We investigated whether the novel EP (prostaglandin E2) receptor agonist ONO-8055 would improve the lower urinary tract dysfunction of neurogenic underactive bladder in a rat lumbar spinal canal stenosis model. MATERIALS AND METHODS First, we studied the agonistic effect of ONO-8055 on EP receptors in EP receptor expressing CHO (Chinese hamster ovary) cells using the increase in the intracellular calcium level and intracellular cAMP (cyclic adenosine monophosphate) production as indicators of receptor activation. The effects of ONO-8055 on bladder and urethral strips from normal rats were then investigated. Finally, the effects of ONO-8055 on bladder and urethral function in rats with lumbar spinal canal stenosis were evaluated by awake cystometry and intraurethral perfusion pressure, respectively. The effects of tamsulosin and distigmine on urethral pressure were also evaluated. RESULTS ONO-8055 is a highly potent and selective agonist for EP2 and EP3 receptors on CHO cells. While this compound contracted bladder strips, it relaxed urethral strips. Awake cystometry showed that ONO-8055 significantly decreased bladder capacity, post-void residual urine and voiding pressure. Compared with vehicle, tamsulosin and ONO-8055 significantly decreased urethral pressure. CONCLUSIONS ONO-8055 decreased post-void residual urine, probably by decreasing bladder capacity. The decrease in voiding pressure probably resulted from the lowered urethral pressure due to relaxation of the urethra. Thus, the novel EP2 and EP3 receptor dual agonist ONO-8055 has the potential to improve neurogenic underactive bladder.
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Sacco E, Recupero S, Bientinesi R, Palermo G, D’Agostino D, Currò D, Bassi P. Pioneering drugs for overactive bladder and detrusor overactivity: Ongoing research and future directions. World J Obstet Gynecol 2015; 4:24-39. [DOI: 10.5317/wjog.v4.i2.24] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/20/2014] [Revised: 01/31/2015] [Accepted: 04/14/2015] [Indexed: 02/05/2023] Open
Abstract
The ongoing research on pioneering drug candidates for the overactive bladder (OAB) aimed to overcome the limitations of currently licensed pharmacotherapies, such as antimuscarinics, β3-adrenergic agents, and botulinum neurotoxin, has been reviewed performing a systematic literature review and web search. The review covers the exploratory agents alternative to available medications for OAB and that may ultimately prove to be therapeutically useful in the future management of OAB patients based on preclinical and early clinical data. It emerges that many alternative pharmacological strategies have been discovered or are under investigation in disease-oriented studies. Several potential therapeutics are known for years but still find obstacles to pass the clinical stages of development, while other completely novel compounds, targeting new pharmacological targets, have been recently discovered and show potential to translate into clinical therapeutic agents for idiopathic and neurogenic OAB syndrome. The global scenario of investigational drugs for OAB gives promise for the development of innovative therapeutics that may ultimately prove effective as first, combined or second-line treatments within a realistic timescale of ten years.
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18
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Sekido N, Kida J, Wakamatsu D, Okada H, Matsuya H. Effects of α1 Antagonist and Cholinesterase Inhibitor on Cystometric Parameters in Lumbar Canal Stenosis Rats With Underactive Bladder. Urology 2014; 84:1248.e9-15. [DOI: 10.1016/j.urology.2014.07.036] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2014] [Revised: 07/03/2014] [Accepted: 07/22/2014] [Indexed: 10/24/2022]
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Matsumoto S, Watanabe M, Hashizume K, Wada N, Hori JI, Kita M, Iwata T, Kakizaki H. Effects of chronic treatment with cilostazol, a phosphodiesterase 3 inhibitor, on female rat bladder in a partial bladder outlet obstruction model. Urology 2014; 83:675.e7-11. [PMID: 24581543 DOI: 10.1016/j.urology.2013.11.030] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2013] [Revised: 10/29/2013] [Accepted: 11/20/2013] [Indexed: 10/25/2022]
Abstract
OBJECTIVE To investigate whether bladder dysfunction after bladder outlet obstruction (BOO) could be altered by treatment with cilostazol, a phosphodiesterase 3 inhibitor (PDE3i). METHODS Twelve-week-old female Sprague-Dawley rats were divided into 5 groups: groups 1 and 2, sham-operated rats and groups 3-5, BOO rats. Group 1 and 3 rats were given normal diet, group 2 and 5 rats were given high-dose PDE3i diet, and group 4 rats were given low-dose PDE3i diet. PDE3i was given within diet from the day of surgery. Four weeks after BOO, the bladder was excised and dissected into 4 longitudinal strips for isometric organ-bath assay. Contractile responses of bladder strips to electrical field stimulation (EFS), carbachol, and potassium chloride (KCl) were determined for each group. RESULTS BOO induced a significant increase in bladder weight in groups 3-5 compared with groups 1 and 2. PDE3i treatment did not affect bladder weight in sham or BOO rats. Contractile forces in response to EFS, carbachol, and KCl in group 3 were about 20%-40% of those in group 1. Contractile responses to EFS or KCl in PDE3i-treated BOO rats were not significantly different from those in group 3. Only high dose of PDE3i treatment in BOO rats caused a statistically significant increase in the response to carbachol compared with group 3. CONCLUSION PDE3i has a small but significant protective effect on the contractile dysfunction induced by a 4-week BOO in rats, although the increase in bladder mass was not altered. PDE3i could be a useful protection against contractile dysfunction of the obstructed bladder.
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Affiliation(s)
- Seiji Matsumoto
- Department of Renal and Urologic Surgery, Asahikawa Medical University, Asahikawa, Hokkaido, Japan.
| | - Masaki Watanabe
- Department of Renal and Urologic Surgery, Asahikawa Medical University, Asahikawa, Hokkaido, Japan
| | - Kazumi Hashizume
- Department of Renal and Urologic Surgery, Asahikawa Medical University, Asahikawa, Hokkaido, Japan
| | - Naoki Wada
- Department of Renal and Urologic Surgery, Asahikawa Medical University, Asahikawa, Hokkaido, Japan
| | - Jun-ichi Hori
- Department of Renal and Urologic Surgery, Asahikawa Medical University, Asahikawa, Hokkaido, Japan
| | - Masafumi Kita
- Department of Renal and Urologic Surgery, Asahikawa Medical University, Asahikawa, Hokkaido, Japan
| | - Tatsuya Iwata
- Department of Renal and Urologic Surgery, Asahikawa Medical University, Asahikawa, Hokkaido, Japan
| | - Hidehiro Kakizaki
- Department of Renal and Urologic Surgery, Asahikawa Medical University, Asahikawa, Hokkaido, Japan
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Ribeiro AS, Fernandes VS, Martínez‐Sáenz A, Martínez P, Barahona MV, Orensanz LM, Blaha I, Serrano‐Margüello D, Bustamante S, Carballido J, García‐Sacristán A, Prieto D, Hernández M. Powerful Relaxation of Phosphodiesterase Type 4 Inhibitor Rolipram in the Pig and Human Bladder Neck. J Sex Med 2014; 11:930-941. [DOI: 10.1111/jsm.12456] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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Xin W, Li N, Cheng Q, Petkov GV. BK channel-mediated relaxation of urinary bladder smooth muscle: a novel paradigm for phosphodiesterase type 4 regulation of bladder function. J Pharmacol Exp Ther 2014; 349:56-65. [PMID: 24459245 PMCID: PMC3965888 DOI: 10.1124/jpet.113.210708] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2013] [Accepted: 01/22/2014] [Indexed: 02/05/2023] Open
Abstract
Elevation of intracellular cAMP and activation of protein kinase A (PKA) lead to activation of large conductance voltage- and Ca(2+)-activated K(+) (BK) channels, thus attenuation of detrusor smooth muscle (DSM) contractility. In this study, we investigated the mechanism by which pharmacological inhibition of cAMP-specific phosphodiesterase 4 (PDE4) with rolipram or Ro-20-1724 (C(15)H(22)N(2)O(3)) suppresses guinea pig DSM excitability and contractility. We used high-speed line-scanning confocal microscopy, ratiometric fluorescence Ca(2+) imaging, and perforated whole-cell patch-clamp techniques on freshly isolated DSM cells, along with isometric tension recordings of DSM isolated strips. Rolipram caused an increase in the frequency of Ca(2+) sparks and the spontaneous transient BK currents (TBKCs), hyperpolarized the cell membrane potential (MP), and decreased the intracellular Ca(2+) levels. Blocking BK channels with paxilline reversed the hyperpolarizing effect of rolipram and depolarized the MP back to the control levels. In the presence of H-89 [N-[2-[[3-(4-bromophenyl)-2-propenyl]amino]ethyl]-5-isoquinolinesulfonamide dihydrochloride], a PKA inhibitor, rolipram did not cause MP hyperpolarization. Rolipram or Ro-20-1724 reduced DSM spontaneous and carbachol-induced phasic contraction amplitude, muscle force, duration, and frequency, and electrical field stimulation-induced contraction amplitude, muscle force, and tone. Paxilline recovered DSM contractility, which was suppressed by pretreatment with PDE4 inhibitors. Rolipram had reduced inhibitory effects on DSM contractility in DSM strips pretreated with paxilline. This study revealed a novel cellular mechanism whereby pharmacological inhibition of PDE4 leads to suppression of guinea pig DSM contractility by increasing the frequency of Ca(2+) sparks and the functionally coupled TBKCs, consequently hyperpolarizing DSM cell MP. Collectively, this decreases the global intracellular Ca(2+) levels and DSM contractility in a BK channel-dependent manner.
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Affiliation(s)
- Wenkuan Xin
- Department of Drug Discovery and Biomedical Sciences, South Carolina College of Pharmacy, University of South Carolina, Columbia, South Carolina (W.X., N.L., Q.C., G.V.P.); and Department of Urology, Fourth Hospital of China Medical University, Shenyang, China (N.L.)
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Zhai K, Chang Y, Wei B, Liu Q, Leblais V, Fischmeister R, Ji G. Phosphodiesterase types 3 and 4 regulate the phasic contraction of neonatal rat bladder smooth myocytes via distinct mechanisms. Cell Signal 2014; 26:1001-10. [PMID: 24463006 DOI: 10.1016/j.cellsig.2014.01.020] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2013] [Revised: 12/20/2013] [Accepted: 01/06/2014] [Indexed: 11/28/2022]
Abstract
Activation of the cyclic AMP (cAMP) pathway reduces bladder contractility. However, the role of phosphodiesterase (PDE) families in regulating this function is poorly understood. Here, we compared the contractile function of the cAMP hydrolyzing PDEs in neonatal rat bladder smooth myocytes. RT-PCR and Western blotting analysis revealed that several isoforms of PDE1-4 were expressed in neonatal rat bladder. While 8-methoxymethyl-3-isobutyl-1-methylxanthine (a PDE1 inhibitor) and BAY-60-7550 (a PDE2 inhibitor) had no effect on the carbachol-enhanced phasic contractions of bladder strips, cilostamide (Cil, a PDE3 inhibitor) and Ro-20-1724 (Ro, a PDE4 inhibitor) significantly reduced these contractions. This inhibitory effect of Ro was blunted by the PKA inhibitor H-89, while the inhibitory effect of Cil was strongly attenuated by the PKG inhibitor KT 5823. Application of Ro in single bladder smooth myocytes resulted in an increase in Ca(2+) spark frequency but a decrease both in Ca(2+) transients and in sarcoplasmic reticulum (SR) Ca(2+) content. In contrast, Cil had no effect on these events. Furthermore, Ro-induced inhibition of the phasic contractions was significantly blocked by ryanodine and iberiotoxin. Taken together, PDE3 and PDE4 are the main PDE isoforms in maintaining the phasic contractions of bladder smooth myocytes, with PDE4 being functionally more active than PDE3. However, their roles are mediated through different mechanisms.
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Affiliation(s)
- Kui Zhai
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China; Inserm UMR-S 769, LabEx LERMIT, F-92296 Châtenay-Malabry, France; Université Paris-Sud, Faculté de Pharmacie, F-92296 Châtenay-Malabry, France
| | - Yan Chang
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Bin Wei
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Qinghua Liu
- Institute for Medical Biology, College of Life Sciences, South-Central University for Nationalities, Wuhan, China
| | - Véronique Leblais
- Inserm UMR-S 769, LabEx LERMIT, F-92296 Châtenay-Malabry, France; Université Paris-Sud, Faculté de Pharmacie, F-92296 Châtenay-Malabry, France
| | - Rodolphe Fischmeister
- Inserm UMR-S 769, LabEx LERMIT, F-92296 Châtenay-Malabry, France; Université Paris-Sud, Faculté de Pharmacie, F-92296 Châtenay-Malabry, France.
| | - Guangju Ji
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China.
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Rahnama'i MS, Ückert S, Hohnen R, van Koeveringe GA. The role of phosphodiesterases in bladder pathophysiology. Nat Rev Urol 2013; 10:414-24. [DOI: 10.1038/nrurol.2013.101] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Kang JY, Kim EK, Kim KM. Effects of mirodenafil, a phosphodiesterase-5 inhibitor, on female rat bladder in a partial bladder outlet obstruction model: physiological and immunohistochemical aspects. Korean J Urol 2013; 54:339-44. [PMID: 23700501 PMCID: PMC3659229 DOI: 10.4111/kju.2013.54.5.339] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2012] [Accepted: 03/11/2013] [Indexed: 01/24/2023] Open
Abstract
Purpose We investigated the effects of mirodenafil, a phosphodiesterase-5 inhibitor developed in South Korea, on the female rat bladder in a partial bladder outlet obstruction (BOO) model. Materials and Methods Thirty-six female Sprague-Dawley rats were divided into four groups: the control group, BOO without medication group, BOO with mirodenafil 1 mg/kg group, and BOO with mirodenafil 4 mg/kg group. Mirodenafil was administered orally for 2 weeks after the induction of BOO. Two weeks after BOO, the rats in each group underwent cystometry under urethane anesthesia. After cystometry, the bladder was excised to perform immunohistochemical staining for connexin 43. Results The three BOO groups showed significant increases in mean bladder weight compared with the control group. Baseline pressure, threshold pressure, and maximum contraction pressure were not significantly different between the four groups. Although the contraction interval was decreased in all BOO groups compared with the control group, it was prolonged in the two groups treated with mirodenafil compared with the untreated BOO group. In the immunohistochemical examination, connexin 43 staining intensity in the lamina propria increased in the three BOO groups compared with the control group. The two groups treated with mirodenafil, however, showed decreased connexin 43 staining compared with the untreated BOO group. Conclusions Mirodenafil may increase the contraction intervals of female rat bladders in a partial BOO model. Decreasing bladder overactivity by mirodenafil may be related to intracellular communication mechanisms involving connexin 43.
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Affiliation(s)
- Jung Yoon Kang
- Department of Urology, Eulji General Hospital, Seoul, Korea
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25
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Sekido N, Jyoraku A, Okada H, Wakamatsu D, Matsuya H, Nishiyama H. A novel animal model of underactive bladder: Analysis of lower urinary tract function in a rat lumbar canal stenosis model. Neurourol Urodyn 2012; 31:1190-6. [DOI: 10.1002/nau.21255] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2011] [Accepted: 11/28/2011] [Indexed: 11/09/2022]
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Xin W, Cheng Q, Soder RP, Petkov GV. Inhibition of phosphodiesterases relaxes detrusor smooth muscle via activation of the large-conductance voltage- and Ca²⁺-activated K⁺ channel. Am J Physiol Cell Physiol 2012; 302:C1361-70. [PMID: 22322973 DOI: 10.1152/ajpcell.00432.2011] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Detrusor smooth muscle (DSM) exhibits increased spontaneous phasic contractions under pathophysiological conditions such as detrusor overactivity (DO). Our previous studies showed that activation of cAMP signaling pathways reduces DSM contractility by increasing the large-conductance voltage- and Ca(2+)-activated K(+) (BK) channel activity. Here, we tested the hypothesis whether inhibition of phosphodiesterases (PDEs) can reduce guinea pig DSM excitability and contractility by increasing BK channel activity. Utilizing isometric tension recordings of DSM isolated strips and the perforated patch-clamp technique on freshly isolated DSM cells, we examined the mechanism of DSM relaxation induced by PDE inhibition. Inhibition of PDEs by 3-isobutyl-1-methylxanthine (IBMX), a nonselective PDE inhibitor, significantly reduced DSM spontaneous and carbachol-induced contraction amplitude, frequency, duration, muscle force integral, and tone in a concentration-dependent manner. IBMX significantly reduced electrical field stimulation-induced contractions of DSM strips. Blocking BK channels with paxilline diminished the inhibitory effects of IBMX on DSM contractility, indicating a role for BK channels in DSM relaxation mediated by PDE inhibition. IBMX increased the transient BK currents (TBKCs) frequency by ∼3-fold without affecting the TBKCs amplitude. IBMX increased the frequency of the spontaneous transient hyperpolarizations by ∼2-fold and hyperpolarized the DSM cell resting membrane potential by ∼6 mV. Blocking the BK channels with paxilline abolished the IBMX hyperpolarizing effects. Under conditions of blocked Ca(2+) sources for BK channel activation, IBMX did not affect the depolarization-induced steady-state whole cell BK currents. Our data reveal that PDE inhibition with IBMX relaxes guinea pig DSM via TBKCs activation and subsequent DSM cell membrane hyperpolarization.
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Affiliation(s)
- Wenkuan Xin
- Department of Pharmaceutical and Biomedical Sciences, South Carolina College of Pharmacy, University of South Carolina, Columbia, South Carolina 29208, USA
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Uckert S, Oelke M. Phosphodiesterase (PDE) inhibitors in the treatment of lower urinary tract dysfunction. Br J Clin Pharmacol 2012; 72:197-204. [PMID: 21745238 DOI: 10.1111/j.1365-2125.2010.03828.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Several disorders of the human upper and lower urinary tract, such as urinary stone disease, lower urinary tract symptoms (LUTS) due to benign prostatic hyperplasia (BPH) and detrusor overactivity, can be therapeutically addressed by influencing the function of the smooth musculature of the ureter, prostate or urinary bladder, respectively. In order to ensure a drug effect without significant adverse events, a certain degree of tissue selectivity is mandatory. The treatment of said conditions aims to focus on orally available drugs acting via intracellular signalling pathways. Specifically, the cyclic nucleotide monophosphate cyclic GMP represents an important mediator in the control of the outflow region (bladder, urethra). The use of phosphodiesterase (PDE) inhibitors, such as sildenafil, tadalafil, vardenafil, avanafil or udenafil, known to restrain the degradation of the second messenger cyclic GMP, offers great opportunities in the treatment of lower urinary tract dysfunction. PDE inhibitors are regarded as efficacious, have a rapid onset of action and favourable effect-to-side-effect ratio. The role of PDE5 inhibitors in the treatment of BPH/LUTS and the overactive bladder has already been addressed in randomized, double-blind, placebo-controlled trials, as well as preliminary open-label studies enrolling either several hundreds or only 20 patients. The purpose of this review is to focus on the potential use and clinical significance of PDE inhibitors in the treatment of storage and voiding dysfunctions of the lower urinary tract. The strategy of modulating the activity of PDE isoenzymes might represent a novel approach in patients with lower urinary tract dysfunction (LUTD).
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Affiliation(s)
- Stefan Uckert
- Hannover Medical School, Division of Surgery, Department of Urology and Urological Oncology, Hannover, Germany.
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Kim SJ, Park EY, Hwang TK, Kim JC. Therapeutic effects of connexin inhibitors on detrusor overactivity induced by bladder outlet obstruction in rats. Urology 2011; 78:475.e1-7. [PMID: 21820587 DOI: 10.1016/j.urology.2011.03.029] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2010] [Revised: 02/24/2011] [Accepted: 03/16/2011] [Indexed: 11/12/2022]
Abstract
OBJECTIVES To investigate the alterations in Connexin 43 (Cx43) and connexin 26 (Cx26) levels in the bladder outlet obstruction (BOO)-induced detrusor overactivity and examine the effect of connexin inhibitors on this condition. METHODS Fifty Sprague-Dawley rats were divided into 4 groups: sham-operated control group (n = 10), BOO group (n = 10), and 2 groups that were administered connexin inhibitors. The first of these 2 groups was administered 18β-glycyrrhetinic acid (BOO-18β-GA group, n = 15) and the second group was given oleamide (BOO-oleamide group, n = 15). Cystometrogram was performed in all groups after 2 weeks of obstruction. The expression levels of Cx26 and Cx43 were analyzed using immunohistochemical staining and Western blot. RESULTS The intercontraction interval was markedly shorter in the BOO group compared with the control group (P <.05). Intercontraction intervals in the BOO-18β-GA and BOO-oleamide groups at 2 weeks were significantly longer than that observed for the BOO group (P <.05). The expression of Cx43 and Cx26 were increased in the BOO group. After administration of connexin inhibitors, downregulation of Cx43 and Cx26 was noted. CONCLUSIONS These results suggest that upregulation of Cx43 and Cx26 induce detrusor overactivity after BOO, and connexin inhibitors may have some role in relieving BOO-induced detrusor overactivity in rats.
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Affiliation(s)
- Su Jin Kim
- Department of Urology, College of Medicine, The Catholic University of Korea, Seoul, Korea
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Bao F, Fleming JC, Golshani R, Pearse DD, Kasabov L, Brown A, Weaver LC. A selective phosphodiesterase-4 inhibitor reduces leukocyte infiltration, oxidative processes, and tissue damage after spinal cord injury. J Neurotrauma 2011; 28:1035-49. [PMID: 21355819 DOI: 10.1089/neu.2010.1575] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
We tested the hypothesis that a selective phosphodiesterase type 4 inhibitor (PDE4-I; IC486051) would attenuate early inflammatory and oxidative processes following spinal cord injury (SCI) when delivered during the first 3 days after injury. Rats receiving a moderately severe thoracic-clip-compression SCI were treated with the PDE4-I (0.5, 1.0, and 3.0 mg/kg IV) in bolus doses from 2-60 h post-injury. Doses at 0.5 mg/kg and 1.0 mg/kg significantly decreased myeloperoxidase (MPO) enzymatic activity (neutrophils), expression of a neutrophil-associated protein and of ED-1 (macrophages), and estimates of lipid peroxidation in cord lesion homogenates at 24 h and 72 h post-injury by 25-40%. The 3.0 mg/kg dose had small or no effects on these measures. The PDE4-I treatment (0.5 or 1.0 mg/kg) reduced expression of the oxidative enzymes gp91(phox), inducible nitric oxide synthase, and cyclooxygenase-2, and diminished free radical generation by up to 40%. Treatment with 0.5 mg/kg PDE4-I improved motor function (as assessed by the Basso-Beattie-Bresnahan scale) significantly from 4-8 weeks after SCI (average difference 1.3 points). Mechanical allodynia elicited from the hindpaw decreased by up to 25%. The PDE4-I treatment also increased white matter volume near the lesion at 8 weeks after SCI. In conclusion, the PDE4-I reduced key markers of oxidative stress and leukocyte infiltration, producing cellular protection, locomotor improvements, and a reduction in neuropathic pain. Early inhibition of PDE4 is neuroprotective after SCI when given acutely and briefly at sufficient doses.
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Affiliation(s)
- Feng Bao
- Spinal Cord Injury Team, Robarts Research Institute, Schulich School of Medicine & Dentistry, University of Western Ontario, London, Ontario, Canada.
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Abstract
AIMS To discuss (1) mechanisms involved in the generation and control of myocyte contractions and consequent afferent nerve activity and (2) these mechanisms as targets for drugs aimed for treatment of overactive bladder (OAB) symptoms and detrusor overactivity (DO). METHODS Literature review of myocyte activation, bladder afferent nerves, mediators in the bladder, and translational aspects of the findings. RESULTS During bladder filling, there is normally no parasympathetic outflow from the spinal cord. Despite this, the bladder develops tone during filling and also exhibits non-synchronized local contractions and relaxations that are caused by a basal myogenic mechanical activity that may be reinforced by release of, for example, acetylcholine from non-neuronal and/or neuronal sources or local mediators, such as prostaglandins and endothelins. It is suggested that these spontaneous contractions are able to generate activity in afferent nerves ("afferent noise") that may contribute to DO and OAB. CONCLUSIONS Spontaneous bladder myocyte contractions and factors that are able to modulate them, as well as the consequent afferent nerve activity, may be targets for drugs meant for treatment of OAB/DO.
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Affiliation(s)
- Karl-Erik Andersson
- Wake Forest Institute for Regenerative Medicine, Wake Forest University School of Medicine, Winston-Salem, North Carolina 27157, USA.
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Patra PB, Thorneloe KS, Laping NJ. Effect of estrogen and progesterone on urodynamics in the conscious rat. Urology 2009; 74:463-6. [PMID: 19573897 DOI: 10.1016/j.urology.2008.12.046] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2008] [Revised: 12/01/2008] [Accepted: 12/18/2008] [Indexed: 11/15/2022]
Abstract
OBJECTIVES To examine the effects of estrogen and/or progesterone on the cystometric profiles obtained using continuous-filling cystometry in the conscious Sprague-Dawley rat. METHODS Sprague-Dawley rats underwent ovariectomy (OVX) and were compared with controls by conscious continuous-filling cystometry. The effect of estrogen (10 microg/kg/d for 14 days) and/or progesterone (10 mg/kg/d for 14 days) replacement on OVX urodynamics was examined (n = 7-8/group). RESULTS OVX rats demonstrated reduced micturition intervals and voided volumes compared with controls. These effects of OVX were reversed by estrogen replacement, but not by progesterone replacement. When combined with estrogen, progesterone functioned to partially antagonize the effects of estrogen in OVX rats. CONCLUSIONS Estrogen enhances bladder capacity in the OVX rat and therefore is a likely contributor to the larger bladder capacity in the female compared with the male rat. Consistent with its established role in reproductive physiology, progesterone antagonizes the beneficial effects of estrogen on OVX rat urodynamics.
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Affiliation(s)
- Phani B Patra
- Cardiovascular and Urogenital Center for Excellence in Drug Discovery, GlaxoSmithKline, King of Prussia, Pennsylvania 19406, USA
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Abstract
Lower urinary tract symptoms (LUTS), overactive bladder syndrome (OAB) and detrusor overactivity (DO) are all conditions that can have major effects on quality of life and social functioning. Antimuscarinic drugs are first-line treatment-they often have good initial response rates, but adverse effects and decreasing efficacy cause long-term compliance problems, and alternatives are needed. The recognition of the functional contribution of the urothelium, the spontaneous myocyte activity during bladder filling, and the diversity of nerve transmitters has sparked interest in both peripheral and central modulation of LUTS/OAB/DO pathophysiology. There may be several new possibilities to treat LUTS/OAB/DO. β(3)-AR agonists (YM178), PDE 5 inhibitors (sildenafil, tadalafil, vardenafil), vitamin D analogs (elocalcitol), combinations (α(1)-AR antagonist + antimuscarinic), and drugs with a central mode of action (tramadol, aprepitant) all have Randomized controlled trial (RCT) documented efficacy. Which of these therapeutic principles will be developed to clinically useful treatments remains to be established.
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Affiliation(s)
- Karl-Erik Andersson
- Wake Forest Institute for Regenerative Medicine, Wake Forest University School of Medicine, Medical Center Boulevard, Winston Salem, NC 27157, USA
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Büyüknacar HS, Kumcu EK, Göçmen C, Onder S. Effect of phosphodiesterase type 4 inhibitor rolipram on cyclophosphamide-induced cystitis in rats. Eur J Pharmacol 2008; 586:293-9. [PMID: 18358472 DOI: 10.1016/j.ejphar.2008.02.022] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2007] [Revised: 12/19/2007] [Accepted: 02/12/2008] [Indexed: 11/28/2022]
Abstract
Cyclophosphamide induces a severe haemorrhagic cystitis characterized by bladder overactivity. The study was conducted to examine effects of a phosphodiesterase 4 (PDE4) inhibitor rolipram on bladder overactivity in rats with cyclophosphamide treatment. 42 female Wistar rats were used. 30 rats received a single i.p. injection of cyclophosphamide, and after 72 h, bladder function was evaluated by (1) in vitro preparations of whole bladders and (2) cystometry with continuous saline infusion under urethane anesthesia. Cyclophosphamide-treatment dramatically potentiated the basal spontaneous contractions of isolated whole bladders compared to control rats. Atropine, guanethidine or suramin was ineffective on the spontaneous contractions whereas nifedipine completely abolished. Rolipram (5-80 microM) induced a significant concentration-dependent decrease on the amplitude, frequency (contractions/min) and area under the curve of spontaneous contractions. Carbachol elicited phasic contractions superimposed on a tonic contraction. Rolipram caused a relaxation on the tonic contraction whereas it could not affect the phasic contractions induced by carbachol. In anesthetized rats, during continuous infusion cystometry, intercontraction interval was significantly shorter in cyclophosphamide-injected rats than in control rats. Rolipram at 5-40 microM has no significant effect on the intercontraction interval and contraction pressure while it significantly decreased pressure threshold. At 80 microM, it significantly decreased the intercontraction interval and contraction pressure. In conclusion, PDE4 inhibitor rolipram caused a significant decrease on the amplitude, frequency and area under the curve of basal spontaneous contractions in cyclophosphamide-treated rats, at doses that have no effect on the carbachol-induced phasic contractions and cystometric parameters. PDE4 inhibitors may be considered as an attractive strategy for the treatment of cyclophosphamide-induced bladder overactivity.
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Affiliation(s)
- Hacer Sinem Büyüknacar
- Department of Pharmacology, School of Medicine, University of Cukurova, Adana, 01330 Turkey
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34
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Andersson KE, Gratzke C. Bladder Pharmacology and Treatment of Lower Urinary Tract Symptoms: Recent Advances. ACTA ACUST UNITED AC 2008. [DOI: 10.3834/uij.1939-4810.2008.07.06] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Kaiho Y, Nishiguchi J, Kwon DD, Chancellor MB, Arai Y, Snyder PB, Yoshimura N. The effects of a type 4 phosphodiesterase inhibitor and the muscarinic cholinergic antagonist tolterodine tartrate on detrusor overactivity in female rats with bladder outlet obstruction. BJU Int 2007; 101:615-20. [PMID: 18070178 DOI: 10.1111/j.1464-410x.2007.07307.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
OBJECTIVE To investigate the effects of the selective phosphodiesterase (PDE) type 4 inhibitor IC485 and the widely used antimuscarinic drug tolterodine tartrate on bladder activity in rats with bladder outlet obstruction (BOO), as inhibition of PDE4 leads to elevation of intracellular cAMP levels and relaxation of smooth muscle. MATERIALS AND METHODS BOO was induced in female Sprague-Dawley rats by tying a silk ligature around the urethra. Six weeks after inducing BOO, conscious rats were assessed by cystometry with the urethral ligature intact. The effects of IC485 (5, 10 and 50 mg/kg intravenous, i.v.) were examined and compared with those of tolterodine (0.01, 0.1 and 1 mg/kg i.v.). RESULTS IC485 (5-50 mg/kg i.v.) decreased the number and amplitude of non-voiding contractions during the storage phase by 63-88% and 49-83%, respectively; IC485 also increased bladder capacity by 28-37%. There was no change in blood pressure after applying IC485. Tolterodine tartrate (0.1 and 1.0 mg/kg) significantly decreased the number and amplitude of non-voiding contractions by 38-74% and 29-44%, respectively, and increased bladder capacity by 19-51%. Whereas voiding efficiency and maximum voiding pressure were not altered by IC485 at any dose, tolterodine significantly reduced both, by 35-67% and 19-34%, respectively. CONCLUSION Both IC485 and tolterodine tartrate reduced detrusor overactivity in rats with BOO. In addition, doses of IC485 that suppressed non-voiding contractions had no effect on voiding function. Therefore, selective PDE4 inhibitors deserve further study as potential agents for treating detrusor overactivity in patients with BOO.
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Affiliation(s)
- Yasuhiro Kaiho
- Department of Urology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15213, USA
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Yoshimura N, Kaiho Y, Miyazato M, Yunoki T, Tai C, Chancellor MB, Tyagi P. Therapeutic receptor targets for lower urinary tract dysfunction. Naunyn Schmiedebergs Arch Pharmacol 2007; 377:437-48. [PMID: 18034230 DOI: 10.1007/s00210-007-0209-z] [Citation(s) in RCA: 111] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2007] [Accepted: 10/22/2007] [Indexed: 01/25/2023]
Abstract
The functions of the lower urinary tract, to store and periodically release urine, are dependent on the activity of smooth and striated muscles in the bladder, urethra, and external urethral sphincter. During urine storage, the outlet is closed, and the bladder smooth muscle is quiescent. When bladder volume reaches the micturition threshold, activation of a micturition center in the dorsolateral pons (the pontine micturition center) induces a bladder contraction and a reciprocal relaxation of the urethra, leading to bladder emptying. During voiding, sacral parasympathetic (pelvic) nerves provide an excitatory input (cholinergic and purinergic) to the bladder and inhibitory input (nitrergic) to the urethra. These peripheral systems are integrated by excitatory and inhibitory regulation at the levels of the spinal cord and the brain. Injury or diseases of the nervous system, as well as drugs and disorders of the peripheral organs, can produce lower urinary tract dysfunction. In the overactive bladder (OAB) condition, therapeutic targets for facilitation of urine storage can be found at the levels of the urothelium, detrusor muscles, autonomic and afferent pathways, spinal cord, and brain. There is increasing evidence showing that the urothelium has specialized sensory and signaling properties including: (1) expression of nicotinic, muscarinic, tachykinin, adrenergic, bradykinin, and transient receptor potential (TRP) receptors, (2) close physical association with afferent nerves, and (3) ability to release chemical molecules such as adenosine triphosphate (ATP), acetylcholine, and nitric oxide. Increased expression and/or sensitivity of these urothelial-sensory molecules that lead to afferent sensitization have been documented as possible pathogenesis of OAB. Targeting afferent pathways and/or bladder smooth muscles by modulating activity of ligand receptors (e.g., neurokinin, ATP, or beta3-adrenergic receptors) and ion channels (e.g., TRPV1 or K) could be effective to suppress OAB. In the stress urinary incontinence condition, pharmacotherapies targeting the neurally mediated urethral continence reflex during stress conditions such as sneezing or coughing could be effective for increasing the outlet resistance. Therapeutic targets include adrenergic and serotonergic receptors in the spinal cord as well as adrenergic receptors at the urethral sphincter, which can enhance urethral reflex activity during stress conditions and increase baseline urethral pressure, respectively.
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Affiliation(s)
- Naoki Yoshimura
- Department of Urology, University of Pittsburgh School of Medicine, Suite 700 Kaufmann Medical Building, 3471 Fifth Avenue, Pittsburgh, PA 15213, USA.
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