1
|
Huang R, Tamalunas A, Waidelich R, Strittmatter F, Stief CG, Hennenberg M. Inhibition of full smooth muscle contraction in isolated human detrusor tissues by mirabegron is limited to off-target inhibition of neurogenic contractions. J Pharmacol Exp Ther 2022; 381:176-187. [DOI: 10.1124/jpet.121.001029] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Accepted: 02/08/2022] [Indexed: 11/22/2022] Open
|
2
|
Rac1 silencing, NSC23766 and EHT1864 reduce growth and actin organization of bladder smooth muscle cells. Life Sci 2020; 261:118468. [PMID: 32961232 DOI: 10.1016/j.lfs.2020.118468] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Revised: 09/07/2020] [Accepted: 09/15/2020] [Indexed: 12/16/2022]
Abstract
AIMS RacGTPase-mediated proliferation and smooth muscle contraction in the lower urinary tract has been recently suggested and may offer putative targets for treamtment of lower urinary tract symptoms. However, RacGTPase function for proliferation of detrusor smooth muscle cells is unknown and the specificity of Rac inhibitors has been questioned. Here, we examined effects of Rac1 knockdown and of the Rac inhibitors NSC23766 and EHT1864 in human bladder smooth muscle cells (hBSMCs). MAIN METHODS Rac1 expression was silenced by shRNA expression. Effects of silencing and Rac inhibitors were assessed by CCK-8 assay, EdU staining, RT-PCR, colony formation assay, flow cytometry, and phalloidin staining. KEY FINDINGS Silencing of Rac1 expression reduced the viability (up to 83% compared to scramble shRNA) and proliferation (virtually completely in proliferation assay), increased apoptosis (124%) and the number of dead cells (51%), and caused breakdown of actin organization (56% reduction of polymerized actin compared to scramble shRNA). Effects on proliferation, viability, and actin organization were mimicked by NSC23766 and EHT1864, while both compounds showed divergent effects on cell death (32-fold increase of dead cells by EHT1864, but not NSC23766). Effects of NSC23766 and EHT1864 on viability of hBSMCs were not altered by Rac1 knockdown. SIGNIFICANCE Rac1 promotes proliferation, viability, and cytoskeletal organization, and suppresses apoptosis in bladder smooth muscle cells, which may be relevant in overactive bladder or diabetes-related bladder dysfunction. NSC23766 and EHT1864 mimick these effects, but may act Rac1-independently, by shared and divergent effects.
Collapse
|
3
|
Li B, Yu Q, Wang R, Gratzke C, Wang X, Spek A, Herlemann A, Tamalunas A, Strittmatter F, Waidelich R, Stief CG, Hennenberg M. Inhibition of Female and Male Human Detrusor Smooth Muscle Contraction by the Rac Inhibitors EHT1864 and NSC23766. Front Pharmacol 2020; 11:409. [PMID: 32317972 PMCID: PMC7154109 DOI: 10.3389/fphar.2020.00409] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Accepted: 03/18/2020] [Indexed: 12/14/2022] Open
Abstract
Introduction Lower urinary tract symptoms (LUTS) due to overactive bladder (OAB) are caused by spontaneous detrusor contractions. Medical treatment with muscarinic receptor antagonists or β3-adrenoceptor agonists aims to inhibit detrusor contractions, but overall results are unsatisfactory. Consequently, improved understanding of bladder smooth muscle contraction and identification of novel compounds for its inhibition are needed to develop alternative options. A role of the GTPase Rac1 for smooth muscle contraction has been reported from the prostate, but is unknown in the human detrusor. Here, we examined effects of the Rac inhibitors NSC23766, which may also antagonize muscarinic receptors, and EHT1864 on contraction of human detrusor tissues. Methods Female and male human detrusor tissues were obtained from radical cystectomy. Effects of NSC23766 (100 µM) and EHT1864 (100 µM) on detrusor contractions were studied in an organ bath. Results Electric field stimulation induced frequency-dependent contractions of detrusor tissues, which were inhibited by NSC23766 and EHT1864. Carbachol induced concentration-dependent contractions. Concentration response curves for carbachol were shifted to the right by NSC23766, reflected by increased EC50 values, but unchanged Emax values. EHT1864 reduced carbachol-induced contractions, resulting in reduced Emax values for carbachol. The thromboxane analog U46619 induced concentration-dependent contractions, which remained unchanged by NSC23766, but were reduced by EHT1864. Conclusions NSC23766 and EHT1864 inhibit female and male human detrusor contractions. NSC23766, but not EHT1864 competitively antagonizes muscarinic receptors. In addition to neurogenic and cholinergic contractions, EHT1864 inhibits thromboxane A2-induced detrusor contractions. The latter may be promising, as the origin of spontaneous detrusor contractions in OAB is noncholinergic. In vivo, both compounds may improve OAB-related LUTS.
Collapse
Affiliation(s)
- Bingsheng Li
- Department of Urology, University Hospital, LMU Munich, Munich, Germany
| | - Qingfeng Yu
- Department of Urology, University Hospital, LMU Munich, Munich, Germany
| | - Ruixiao Wang
- Department of Urology, University Hospital, LMU Munich, Munich, Germany
| | - Christian Gratzke
- Department of Urology, University Hospital, LMU Munich, Munich, Germany.,Department of Urology, University of Freiburg, Freiburg, Germany
| | - Xiaolong Wang
- Department of Urology, University Hospital, LMU Munich, Munich, Germany
| | - Annabel Spek
- Department of Urology, University Hospital, LMU Munich, Munich, Germany
| | - Annika Herlemann
- Department of Urology, University Hospital, LMU Munich, Munich, Germany
| | | | | | | | - Christian G Stief
- Department of Urology, University Hospital, LMU Munich, Munich, Germany
| | - Martin Hennenberg
- Department of Urology, University Hospital, LMU Munich, Munich, Germany
| |
Collapse
|
4
|
West EG, Sellers DJ, Chess-Williams R, McDermott C. Voiding Behavior and Efferent Bladder Function Altered in Mice Following Social Defeat but Not Witness Trauma. Front Physiol 2020; 11:247. [PMID: 32265738 PMCID: PMC7098992 DOI: 10.3389/fphys.2020.00247] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Accepted: 03/04/2020] [Indexed: 12/31/2022] Open
Abstract
Psychological stress is associated with bladder dysfunction, however, the local bladder mechanisms affected are not well understood. This study aimed to determine how psychological stress, caused by social defeat or witness trauma, affects voiding behavior and bladder function. Pairs of male C57Bl/6J mice were placed in a custom-made plexiglass chamber with an aggressor ARC(S) mouse for 1 h/day for 10 days. The social defeat mouse was in physical contact with the aggressor, while the witness was physically separated but could observe interactions between its cage-mate and the aggressor. Age matched control pairs were used for comparison. Voiding analysis was conducted periodically over the 10 days. An ex vivo whole bladder preparation was used to assess functional changes after the period of stress. Plasma corticosterone levels were significantly increased by both social defeat and witness trauma stress when compared to unstressed controls. Voiding analysis revealed a significant decrease in voiding frequency in the social defeat group compared to control animals, indicating an altered voiding phenotype. Witness trauma did not alter voiding behavior. Bladder contractile responses to cholinergic stimulation were not significantly altered in either stress group, nor was relaxation to the beta-adrenoceptor agonist isoprenaline. However, nerve evoked contractile responses were significantly increased at all frequencies in bladders from social defeat but not witness trauma mice. Purinergic contractile responses were also significantly enhanced in this group. Social defeat also resulted in increased urothelial acetylcholine release during bladder distension, with no change in ATP release. In conclusion, functional bladder changes are dependent upon stressor type. Enhanced urothelial acetylcholine may desensitize bladder sensory nerves, which, coupled with more efficient voiding contractions due to enhanced nerve-mediated and purinergic detrusor responses, may account for the altered voiding phenotype observed. This study reports a male model of social defeat stress with reduced urinary frequency, with no voiding changes observed in the witness.
Collapse
Affiliation(s)
- Eliza G West
- Centre for Urology Research, Faculty of Health Sciences and Medicine, Bond University, Robina, QLD, Australia
| | - Donna J Sellers
- Centre for Urology Research, Faculty of Health Sciences and Medicine, Bond University, Robina, QLD, Australia
| | - Russ Chess-Williams
- Centre for Urology Research, Faculty of Health Sciences and Medicine, Bond University, Robina, QLD, Australia
| | - Catherine McDermott
- Centre for Urology Research, Faculty of Health Sciences and Medicine, Bond University, Robina, QLD, Australia
| |
Collapse
|
5
|
Li B, Wang X, Rutz B, Wang R, Tamalunas A, Strittmatter F, Waidelich R, Stief CG, Hennenberg M. The STK16 inhibitor STK16-IN-1 inhibits non-adrenergic and non-neurogenic smooth muscle contractions in the human prostate and the human male detrusor. Naunyn Schmiedebergs Arch Pharmacol 2019; 393:829-842. [PMID: 31867686 DOI: 10.1007/s00210-019-01797-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Accepted: 12/12/2019] [Indexed: 01/25/2023]
Abstract
Mixed lower urinary tract symptoms (LUTS) (voiding symptoms suggestive of benign prostatic hyperplasia plus storage symptoms, which can be caused by overactive bladder) are common in men. Unwanted contraction of prostate and/or bladder smooth muscle has been implied in the pathophysiology of male LUTS. Here, we examined effects of the serine/threonine kinase 16 (STK16) inhibitor STK16-IN-1 on contraction of human tissues from the prostate and male detrusor. Tissues were obtained from radical prostatectomy and radical cystectomy. Contractions were studied in an organ bath and STK16 expressions by Western blot analyses and fluorescence staining. In prostate tissues, STK16-IN-1 (1 μM) inhibited contractions induced by endothelin-1 and the thromboxane A2 analog U46619. Contractions of prostate tissues induced by noradrenaline, the α1-agonists phenylephrine and methoxamine, or electric field stimulation (EFS) were not changed by STK16-IN-1. In male detrusor tissues, STK16-IN-1 inhibited contractions induced by the cholinergic agonists carbachol and metacholine, and contractions induced by U46619. EFS-induced contractions of detrusor tissues were not changed by STK16-IN-1. Western blot analyses of prostate and detrusor tissues revealed bands matching the molecular weight of STK16. Fluorescence staining of prostate tissues using STK16 antibodies resulted in immunoreactivity in smooth muscle cells. STK16-IN-1 selectively inhibits non-adrenergic/non-neurogenic smooth muscle contractions in the male prostate and to limited extent in the bladder. Because non-adrenergic contractions in the male LUTS may account for limited efficacy of α1-blockers and for α1-blocker-resistant symptoms, studies assessing add-on of STK16-IN-1 to α1-blockers in mixed LUTS appear feasible.
Collapse
Affiliation(s)
- Bingsheng Li
- Department of Urology, University Hospital, LMU Munich, Munich, Germany
| | - Xiaolong Wang
- Department of Urology, University Hospital, LMU Munich, Munich, Germany
| | - Beata Rutz
- Department of Urology, University Hospital, LMU Munich, Munich, Germany
| | - Ruixiao Wang
- Department of Urology, University Hospital, LMU Munich, Munich, Germany
| | | | | | | | - Christian G Stief
- Department of Urology, University Hospital, LMU Munich, Munich, Germany
| | - Martin Hennenberg
- Department of Urology, University Hospital, LMU Munich, Munich, Germany. .,Urologische Klinik und Poliklinik, LMU Munich, Marchioninistr. 15, 81377, Munich, Germany.
| |
Collapse
|
6
|
Fry CH, McCloskey KD. Spontaneous Activity and the Urinary Bladder. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1124:121-147. [PMID: 31183825 DOI: 10.1007/978-981-13-5895-1_5] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The urinary bladder has two functions: to store urine, when it is relaxed and highly compliant; and void its contents, when intravesical pressure rises due to co-ordinated contraction of detrusor smooth muscle in the bladder wall. Superimposed on this description are two observations: (1) the normal, relaxed bladder develops small transient increases of intravesical pressure, mirrored by local bladder wall movements; (2) pathological, larger pressure variations (detrusor overactivity) can occur that may cause involuntary urine loss and/or detrusor overactivity. Characterisation of these spontaneous contractions is important to understand: how normal bladder compliance is maintained during filling; and the pathophysiology of detrusor overactivity. Consideration of how spontaneous contractions originate should include the structural complexity of the bladder wall. Detrusor smooth muscle layer is overlain by a mucosa, itself a complex structure of urothelium and a lamina propria containing sensory nerves, micro-vasculature, interstitial cells and diffuse muscular elements.Several theories, not mutually exclusive, have been advanced for the origin of spontaneous contractions. These include intrinsic rhythmicity of detrusor muscle; modulation by non-muscular pacemaking cells in the bladder wall; motor input to detrusor by autonomic nerves; regulation of detrusor muscle excitability and contractility by the adjacent mucosa and spontaneous contraction of elements of the lamina propria. This chapter will consider evidence for each theory in both normal and overactive bladder and how their significance may vary during ageing and development. Further understanding of these mechanisms may also identify novel drug targets to ameliorate the clinical consequences of large contractions associated with detrusor overactivity.
Collapse
Affiliation(s)
- Christopher H Fry
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, UK.
| | - Karen D McCloskey
- School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, UK
| |
Collapse
|
7
|
Kullmann FA, Beckel JM, McDonnell B, Gauthier C, Lynn AM, Wolf-Johnston A, Kanai A, Zabbarova IV, Ikeda Y, de Groat WC, Birder LA. Involvement of TRPM4 in detrusor overactivity following spinal cord transection in mice. NAUNYN-SCHMIEDEBERG'S ARCHIVES OF PHARMACOLOGY 2018; 391:1191-1202. [PMID: 30054681 PMCID: PMC6186176 DOI: 10.1007/s00210-018-1542-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2018] [Accepted: 07/17/2018] [Indexed: 12/31/2022]
Abstract
Transient receptor potential cation channel subfamily M member 4 (TRPM4) has been shown to play a key role in detrusor contractility under physiological conditions. In this study, we investigated the potential role of TRPM4 in detrusor overactivity following spinal cord transection (SCT) in mice. TRPM4 expression and function were evaluated in bladder tissue with or without the mucosa from spinal intact (SI) and SCT female mice (T8-T9 vertebra; 1-28 days post SCT) using PCR, western blot, immunohistochemistry, and muscle strip contractility techniques. TRPM4 was expressed in the urothelium (UT) and detrusor smooth muscle (DSM) and was upregulated after SCT. Expression levels peaked 3-7 days post SCT in both the UT and DSM. Pharmacological block of TRPM4 with the antagonist, 9-Phenanthrol (30 μM) greatly reduced spontaneous phasic activity that developed after SCT, regardless of the presence or absence of the mucosa. Detrusor overactivity following spinal cord injury leads to incontinence and/or renal impairment and represents a major health problem for which current treatments are not satisfactory. Augmented TRPM4 expression in the bladder after chronic SCT supports the hypothesis that TRPM4 channels play a role in DSM overactivity following SCT. Inhibition of TRPM4 may be beneficial for improving detrusor overactivity in SCI.
Collapse
Affiliation(s)
- F Aura Kullmann
- Department of Medicine/Renal and Electrolyte Division, University of Pittsburgh School of Medicine, Pittsburgh, PA, 15261, USA.
| | - Jonathan M Beckel
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, 15261, USA
| | - Bronagh McDonnell
- Department of Medicine/Renal and Electrolyte Division, University of Pittsburgh School of Medicine, Pittsburgh, PA, 15261, USA
| | - Christian Gauthier
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA, 15260, USA
| | - Andrew M Lynn
- Department of Medicine/Renal and Electrolyte Division, University of Pittsburgh School of Medicine, Pittsburgh, PA, 15261, USA
| | - Amanda Wolf-Johnston
- Department of Medicine/Renal and Electrolyte Division, University of Pittsburgh School of Medicine, Pittsburgh, PA, 15261, USA
| | - Anthony Kanai
- Department of Medicine/Renal and Electrolyte Division, University of Pittsburgh School of Medicine, Pittsburgh, PA, 15261, USA
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, 15261, USA
| | - Irina V Zabbarova
- Department of Medicine/Renal and Electrolyte Division, University of Pittsburgh School of Medicine, Pittsburgh, PA, 15261, USA
| | - Youko Ikeda
- Department of Medicine/Renal and Electrolyte Division, University of Pittsburgh School of Medicine, Pittsburgh, PA, 15261, USA
| | - William C de Groat
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, 15261, USA
| | - Lori A Birder
- Department of Medicine/Renal and Electrolyte Division, University of Pittsburgh School of Medicine, Pittsburgh, PA, 15261, USA
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, 15261, USA
| |
Collapse
|
8
|
Modulation of lower urinary tract smooth muscle contraction and relaxation by the urothelium. NAUNYN-SCHMIEDEBERG'S ARCHIVES OF PHARMACOLOGY 2018; 391:675-694. [DOI: 10.1007/s00210-018-1510-8] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2018] [Accepted: 05/08/2018] [Indexed: 10/14/2022]
|
9
|
Regulation of Spontaneous Contractions in Intact Rat Bladder Strips and the Effects of Hydrogen Peroxide. BIOMED RESEARCH INTERNATIONAL 2018; 2018:2925985. [PMID: 29511675 PMCID: PMC5817331 DOI: 10.1155/2018/2925985] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Revised: 12/01/2017] [Accepted: 12/31/2017] [Indexed: 01/07/2023]
Abstract
Enhanced spontaneous contractions are associated with overactive bladder. Elevated levels of reactive oxygen species might contribute to enhanced spontaneous contractions. We investigated the regulation of spontaneous contractions and the effects of hydrogen peroxide (H2O2) in intact rat bladder strips. The spontaneous contractions were measured using a tissue bath system. The vehicle or the specific activators/blockers were applied and followed by the application of 0.003 g% H2O2. The basal tension, amplitude, and frequency of spontaneous contractions were quantified. Nisoldipine and bisindolylmaleimide 1 had no effects on spontaneous contractions. SKF96365 and Y27632 decreased basal tension and amplitude. Ryanodine slightly increased frequency. Both iberiotoxin and NS-1619 increased amplitude. Apamin reduced frequency but increased amplitude. NS-309 inhibited both the amplitude and frequency. The basal tension and amplitude increased when H2O2 was applied. Pretreatment with NS-309 inhibited H2O2-elicited augmented amplitude and frequency, while pretreatment with Y-27632 inhibited the augmented basal tension. The combined application of NS-309 and Y27632 almost eliminated spontaneous contractions and its augmentation induced by H2O2. In conclusion, Ca2+ influx, Rho kinase activation, and SK channel inactivation play important roles in spontaneous contractions in intact bladder strips, whereas only latter two mechanisms may be involved in H2O2-elicited increased spontaneous contractions.
Collapse
|
10
|
Kuga N, Tanioka A, Hagihara K, Kawai T. Fiber type-specific afferent nerve activity induced by transient contractions of rat bladder smooth muscle in pathological states. PLoS One 2017; 12:e0189941. [PMID: 29267380 PMCID: PMC5739434 DOI: 10.1371/journal.pone.0189941] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2017] [Accepted: 11/18/2017] [Indexed: 11/20/2022] Open
Abstract
Bladder smooth muscle shows spontaneous phasic contractions, which undergo a variety of abnormal changes depending on pathological conditions. How abnormal contractions affect the activity of bladder afferent nerves remains to be fully tested. In this study, we examined the relationship between transient increases in bladder pressure, representing transient contraction of bladder smooth muscle, and spiking patterns of bladder afferent fibers of the L6 dorsal root, in rat pathological models. All recordings were performed at a bladder pressure of approximately 10 cmH2O by maintaining the degree of bladder filling. In the cyclophosphamide-induced model, both Aδ and C fibers showed increased sensitivity to transient bladder pressure increases. In the prostaglandin E2-induced model, Aδ fibers, but not C fibers, specifically showed overexcitation that was time-locked with transient bladder pressure increases. These fiber type-specific changes in nerve spike patterns may underlie the symptoms of urinary bladder diseases.
Collapse
Affiliation(s)
- Nahoko Kuga
- Pharmacology Research Laboratory, Watarase Research Center, Kyorin Pharmaceutical Company, Limited, Nogi, Tochigi, Japan
| | - Asao Tanioka
- Pharmacology Research Laboratory, Watarase Research Center, Kyorin Pharmaceutical Company, Limited, Nogi, Tochigi, Japan
| | - Koichiro Hagihara
- Pharmacology Research Laboratory, Watarase Research Center, Kyorin Pharmaceutical Company, Limited, Nogi, Tochigi, Japan
| | - Tomoyuki Kawai
- Pharmacology Research Laboratory, Watarase Research Center, Kyorin Pharmaceutical Company, Limited, Nogi, Tochigi, Japan
- * E-mail:
| |
Collapse
|
11
|
Janssen DAW, Schalken JA, Heesakkers JPFA. Urothelium update: how the bladder mucosa measures bladder filling. Acta Physiol (Oxf) 2017; 220:201-217. [PMID: 27804256 DOI: 10.1111/apha.12824] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2016] [Revised: 07/18/2016] [Accepted: 10/26/2016] [Indexed: 12/20/2022]
Abstract
AIM This review critically evaluates the evidence on mechanoreceptors and pathways in the bladder urothelium that are involved in normal bladder filling signalling. METHODS Evidence from in vitro and in vivo studies on (i) signalling pathways like the adenosine triphosphate pathway, cholinergic pathway and nitric oxide and adrenergic pathway, and (ii) different urothelial receptors that are involved in bladder filling signalling like purinergic receptors, sodium channels and TRP channels will be evaluated. Other potential pathways and receptors will also be discussed. RESULTS Bladder filling results in continuous changes in bladder wall stretch and exposure to urine. Both barrier and afferent signalling functions in the urothelium are constantly adapting to cope with these dynamics. Current evidence shows that the bladder mucosa hosts essential pathways and receptors that mediate bladder filling signalling. Intracellular calcium ion increase is a dominant factor in this signalling process. However, there is still no complete understanding how interacting receptors and pathways create a bladder filling signal. Currently, there are still novel receptors investigated that could also be participating in bladder filling signalling. CONCLUSIONS Normal bladder filling sensation is dependent on multiple interacting mechanoreceptors and signalling pathways. Research efforts need to focus on how these pathways and receptors interact to fully understand normal bladder filling signalling.
Collapse
Affiliation(s)
- D. A. W. Janssen
- Department of Urology; Radboud University Nijmegen Medical Centre; Nijmegen The Netherlands
| | - J. A. Schalken
- Department of Urology; Radboud University Nijmegen Medical Centre; Nijmegen The Netherlands
| | - J. P. F. A. Heesakkers
- Department of Urology; Radboud University Nijmegen Medical Centre; Nijmegen The Netherlands
| |
Collapse
|
12
|
Hennenberg M, Tamalunas A, Wang Y, Keller P, Schott M, Strittmatter F, Herlemann A, Yu Q, Rutz B, Ciotkowska A, Stief CG, Gratzke C. Inhibition of agonist-induced smooth muscle contraction by picotamide in the male human lower urinary tract outflow region. Eur J Pharmacol 2017; 803:39-47. [DOI: 10.1016/j.ejphar.2017.03.022] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Revised: 03/08/2017] [Accepted: 03/13/2017] [Indexed: 10/20/2022]
|
13
|
Bravo G, Massa H, Rose'Meyer R, Chess-Williams R, McDermott C, Sellers DJ. Effect of short-term androgen deficiency on bladder contractility and urothelial mediator release. Naunyn Schmiedebergs Arch Pharmacol 2017; 390:547-556. [PMID: 28190243 DOI: 10.1007/s00210-017-1355-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Accepted: 01/31/2017] [Indexed: 01/23/2023]
Abstract
In men, testosterone levels decline by 1% per year after the age of 40. Reduced androgen levels may directly contribute to lower urinary tract symptoms and bladder dysfunction, although the mechanisms are unclear. This study examined the effect of low testosterone and testosterone replacement on key mechanisms involved in local bladder function. Intraluminal release of the mediators ATP and ACh in response to bladder distension was measured in whole bladders from rats 8 weeks following castration, whilst bladder contractility was assessed using isolated strips. Human urothelial cells were cultured under low, physiological and supra-physiological testosterone conditions for 24 h or 5 days, and stretch-induced release of ATP and ACh was measured. Phasic contractile activity of bladder strips, agonist-induced reponses to carbachol and isoprenaline and nerve-evoked contractions were unaffected by castration. The acetylcholinesterase inhibitor neostigmine significantly increased amplitude of phasic activity only in bladder strips following castration, and this was prevented by testosterone replacement. Intraluminal ACh release following bladder distension was significantly reduced following castration, whilst ATP release was unaffected. In contrast, stretch-induced ATP release from urothelial cells was significantly enhanced in low testosterone conditions, whilst ACh release was unaltered. Testosterone-replacement to physiological levels prevented these changes. Whilst androgen deficiency of 8 weeks does not directly affect contractility of bladder smooth muscle, urothelial mediator release is sensitive to changes in testosterone. These changes in mediator release may be an early effect of the decline in testosterone and could affect sensory pathways in the longer term, contributing to the urinary symptoms and bladder dysfunction seen in androgen-deficient men.
Collapse
Affiliation(s)
- Giselle Bravo
- Centre for Urology Research, Faculty of Health Sciences and Medicine, Bond University, Queensland, Australia
| | - Helen Massa
- School of Medical Science, Griffith University, Queensland, Australia
| | | | - Russ Chess-Williams
- Centre for Urology Research, Faculty of Health Sciences and Medicine, Bond University, Queensland, Australia
| | - Catherine McDermott
- Centre for Urology Research, Faculty of Health Sciences and Medicine, Bond University, Queensland, Australia
| | - Donna J Sellers
- Centre for Urology Research, Faculty of Health Sciences and Medicine, Bond University, Queensland, Australia.
| |
Collapse
|
14
|
Akino H. Spontaneous Contractile Activity of the Detrusor Muscle and Its Role in the Pathogenesis of Overactive Bladder Syndrome. Low Urin Tract Symptoms 2015; 4 Suppl 1:42-7. [PMID: 26676699 DOI: 10.1111/j.1757-5672.2011.00117.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
There is accumulated evidence that spontaneous contractions (SCs) in the bladder wall are associated with afferent nerve firing in the bladder. The role of the urothelium in bladder sensation might be restricted to pathological conditions, such as interstitial cystitis or chemical cystitis in which the release of urothelium-derived mediators such as adenosine triphosphate is increased. Recent publications imply that SCs in bladders with detrusor overactivity due to spinal cord injury or bladder outlet obstruction are modulated by intracellular signal transduction mechanisms such as the RhoA/Rho-kinase pathway, denervation-supersensitivity to acetylcholine, changes in ion channel activity, enhanced gap-junctional intercellular communication, alterations in interstitial cells of Cajal, the actions of local mediators in the detrusor and the influence of the urothelium. Spontaneous contractions and possible consequent afferent nerve firing might participate in the generation of overactive bladder syndrome.
Collapse
Affiliation(s)
- Hironobu Akino
- Department of Urology, Medical Science, University of Fukui, Yoshida, Japan
| |
Collapse
|
15
|
Enhanced urothelial ATP release and contraction following intravesical treatment with the cytotoxic drug, doxorubicin. Naunyn Schmiedebergs Arch Pharmacol 2015; 388:773-80. [PMID: 25683587 DOI: 10.1007/s00210-015-1097-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2014] [Accepted: 01/26/2015] [Indexed: 01/09/2023]
Abstract
Intravesical administration of the cytotoxic drug doxorubicin is a common treatment for superficial carcinoma of the bladder, but it is associated with significant urological adverse effects. The aim of this study was to identify doxorubicin-induced changes in the local mechanisms involved in regulating bladder function. As a model of intravesical doxorubicin administration in patients, doxorubicin (1 mg/mL) was applied to the luminal surface of porcine bladders for 60 min. Following treatment, the release of urothelial/lamina propria mediators (acetylcholine (Ach), ATP and prostaglandin E2 (PGE2) and contractile responses of isolated tissue strips was investigated. Doxorubicin pretreatment did not affect contractile responses of detrusor muscle to carbachol, but did enhance neurogenic detrusor responses to electrical field stimulation (219 % at 5 Hz). Contractions of isolated strips of urothelium/lamina propria to carbachol were also enhanced (30 %) in tissues from doxorubicin pretreated bladders. Isolated strips of urothelium/lamina propria from control bladders demonstrated a basal release of all three mediators (Ach > ATP > PGE2), with increased release of ATP when tissues were stretched. In tissues from doxorubicin-pretreated bladders, the basal release of ATP was significantly enhanced (sevenfold), while the release of acetylcholine and PGE2 was not affected. The application of luminal doxorubicin, under conditions that mimic intravesical administration to patients, affects urothelial/lamina propria function (increased contractile activity and ATP release) and enhances efferent neurotransmission without affecting detrusor smooth muscle. These actions would enhance bladder contractile activity and sensory nerve activity and may explain the adverse urological effects observed in patients following intravesical doxorubicin treatment.
Collapse
|
16
|
Fry CH, Jabr RI. T-type Ca2+ channels and the urinary and male genital tracts. Pflugers Arch 2014; 466:781-9. [PMID: 24463704 DOI: 10.1007/s00424-014-1446-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2013] [Revised: 01/06/2014] [Accepted: 01/07/2014] [Indexed: 11/26/2022]
Abstract
T-type Ca(2+) channels are widely expressed throughout the urinary and male genital tracts, generally alongside L-type Ca(2+) channels. The use of pharmacological blockers of these channels has suggested functional roles in all regions, with the possible exception of the ureter. Their functional expression is apparent not just in smooth muscle cells but also in interstitial cells that lie in close proximity to muscle, nerve and epithelial components of these tissues. Thus, T-type Ca(2+) channels can contribute directly to modulation of muscle function and indirectly to changes of epithelial and nerve function. T-type Ca(2+) channel activity modulates phasic contractile activity, especially in conjunction with Ca(2+)-activated K(+) channels, and also to agonist-dependent responses in different tissues. Upregulation of channel density occurs in pathological conditions associated with enhanced contractile responses, e.g. overactive bladder, but it is unclear if this is causal or a response to the pathological state. Moreover, T-type Ca(2+) channels may have a role in the development of prostate tumours regulating the secretion of mitogens from neuroendocrine cells. Although a number of selective channel blockers exist, their relative selectivity over L-type Ca(2+) channels is often low and makes evaluation of T-type Ca(2+) channel function in the whole organism difficult.
Collapse
Affiliation(s)
- C H Fry
- Department of Biochemistry and Physiology, University of Surrey, Guildford, GU2 7XH, UK,
| | | |
Collapse
|
17
|
Bahadory F, Moore KH, Liu L, Burcher E. Gene expression of muscarinic, tachykinin, and purinergic receptors in porcine bladder: comparison with cultured cells. Front Pharmacol 2013; 4:148. [PMID: 24348420 PMCID: PMC3842897 DOI: 10.3389/fphar.2013.00148] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2013] [Accepted: 11/10/2013] [Indexed: 12/04/2022] Open
Abstract
Urothelial cells, myofibroblasts, and smooth muscle cells are important cell types contributing to bladder function. Multiple receptors including muscarinic (M3/M5), tachykinin (NK1/NK2), and purinergic (P2X1/P2Y6) receptors are involved in bladder motor and sensory actions. Using female pig bladder, our aim was to differentiate between various cell types in bladder by genetic markers. We compared the molecular expression pattern between the fresh tissue layers and their cultured cell counterparts. We also examined responses to agonists for these receptors in cultured cells. Urothelial, suburothelial (myofibroblasts), and smooth muscle cells isolated from pig bladder were cultured (10–14 days) and identified by marker antibodies. Gene (mRNA) expression level was demonstrated by real-time PCR. The receptor expression pattern was very similar between suburothelium and detrusor, and higher than urothelium. The gene expression of all receptors decreased in culture compared with the fresh tissue, although the reduction in cultured urothelial cells appeared less significant compared to suburothelial and detrusor cells. Cultured myofibroblasts and detrusor cells did not contract in response to the agonists acetylcholine, neurokinin A, and β,γ-MeATP, up to concentrations of 0.1 and 1 mM. The significant reduction of M3, NK2, and P2X1 receptors under culture conditions may be associated with the unresponsiveness of cultured suburothelial and detrusor cells to their respective agonists. These results suggest that under culture conditions, bladder cells lose the receptors that are involved in contraction, as this function is no longer required. The study provides further evidence that cultured cells do not necessarily mimic the actions exerted by intact tissues.
Collapse
Affiliation(s)
- Forough Bahadory
- Department of Pharmacology, School of Medical Sciences, University of New South Wales Sydney, NSW, Australia
| | - Kate H Moore
- Detrusor Muscle Laboratory, St. George Hospital, University of New South Wales Kogarah, NSW, Australia
| | - Lu Liu
- Department of Pharmacology, School of Medical Sciences, University of New South Wales Sydney, NSW, Australia
| | - Elizabeth Burcher
- Department of Pharmacology, School of Medical Sciences, University of New South Wales Sydney, NSW, Australia
| |
Collapse
|
18
|
Wang M, Zhang N, Wang W, Wang B, Xu Z, Yang Y. Expression and function of vascular endothelial growth inhibitor in aged porcine bladder detrusor muscle cells. Biogerontology 2013; 14:543-56. [PMID: 24030243 DOI: 10.1007/s10522-013-9460-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2013] [Accepted: 08/27/2013] [Indexed: 01/12/2023]
Abstract
Aging of the bladder detrusor muscle plays an important role in lower urinary tract symptoms in elderly people. Our previous work demonstrated that elderly patients have increased levels of vascular endothelial growth inhibitor (VEGI) in bladder tissue. Therefore, we hypothesized that VEGI may play a role in aging of the bladder detrusor muscle cells. This study aims to develop and characterize primary cultures of aged porcine bladder detrusor muscle cells in order to explore the expression and function of VEGI. Bladder samples from female pigs were divided into two groups: the aged group (Model) and the young group (Control). We confirmed β-galactosidase expression, a marker for senescence, in aged muscle cells (identified by α-smooth muscle actin (α-SMA) staining), but not in the young group. mRNA levels of VEGI-251 and death receptor 3 (DR3) were up-regulated (P < 0.05) and total cell protein levels of VEGI-251, DR3 and nuclear factor-kappa B [NF-κB (p65)], membrane protein levels of DR3, and nuclear protein levels of NF-κB (p65) were significantly higher (P < 0.01) in the Model cells compared to Control cells. In conclusion, we have established a method to culture aged detrusor muscle cells derived from porcine bladder. Higher levels of VEGI-251, DR3 and NF-κB (p65) were observed in the aged cells. VEGI-251 may function by increasing DR3 on cellular membranes and promoting the transfer of NF-κB into the nucleus. This suggests that VEGI may be a target for reversing the aging process of bladder detrusor muscle cells.
Collapse
Affiliation(s)
- Mingqing Wang
- Urology Department, Beijing Chaoyang Hospital, Capital Medical University, No. 8, Gongti South Road, Chaoyang District, Beijing, 100020, People's Republic of China
| | | | | | | | | | | |
Collapse
|
19
|
McDermott C, Chess-Williams R, Mills K, Kang S, Farr S, Grant G, Perkins A, Davey A, Anoopkumar-Dukie S. Alterations in acetylcholine, PGE2 and IL6 release from urothelial cells following treatment with pyocyanin and lipopolysaccharide. Toxicol In Vitro 2013; 27:1693-8. [DOI: 10.1016/j.tiv.2013.04.015] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2013] [Revised: 03/27/2013] [Accepted: 04/20/2013] [Indexed: 10/26/2022]
|
20
|
Klausner AP, King AB, Byrne MD, Habibi JR, Li K, Sabarwal V, Speich JE, Ratz PH. A new and automated method for objective analysis of detrusor rhythm during the filling phase. World J Urol 2013; 32:85-90. [PMID: 23633125 DOI: 10.1007/s00345-013-1084-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2013] [Accepted: 04/18/2013] [Indexed: 11/29/2022] Open
Abstract
INTRODUCTION There is growing acceptance that the detrusor muscle is not silent during the filling phase of the micturition cycle but displays low-amplitude phasic contractions that have been associated with urinary urgency. Unfortunately, there is currently no standardized methodology to quantify detrusor rhythm during the filling phase. Therefore, the purpose of this study was to develop an automated computer algorithm to analyze rat detrusor rhythm in a quick, accurate, and reproducible manner. MATERIALS AND METHODS Strips of detrusor smooth muscle from rats (n = 17) were placed on force transducers and subjected to escalating doses of PGE2 to generate contractile rhythm tracings. An automated computer algorithm was developed to analyze contractile frequency, amplitude, and tone on the generated rhythm tracings. Results of the automated computerized analysis were compared to human (n = 3) interpretations. Human interpreters manually counted contractions and then recounted the same data two weeks later. Intra-observer, inter-observer, and human-to-computer comparisons were performed. RESULTS The computer algorithm quantified concentration-dependent changes in contractile frequency, amplitude, and tone after administration of PGE2 (10(-9)-10(-6)M). Concentration-response curves were similar for all contractile components with increases in frequency identified mainly at physiologic concentrations of PGE2 and increases in amplitude at supra-physiologic concentrations. The computer algorithm consistently over-counted the human interpreters, but with less variability. Differences in inter-observer consistency were statistically significant. CONCLUSIONS Our computerized algorithm accurately and consistently identified changes in detrusor muscle contractile frequency, amplitude, and tone with varying doses of PGE2. Frequency counts were consistently higher than those obtained by human interpreters but without variability or bias. Refinements of this method may allow for more standardized approach in the study of pharmacologic agents on filling phase rhythmic activity.
Collapse
Affiliation(s)
- Adam P Klausner
- Department of Surgery/Division of Urology, Virginia Commonwealth University School of Medicine, PO BOX 980118, Richmond, VA, 23298-0118, USA,
| | | | | | | | | | | | | | | |
Collapse
|
21
|
Phasic contractions in urinary bladder from juvenile versus adult pigs. PLoS One 2013; 8:e58611. [PMID: 23516515 PMCID: PMC3596269 DOI: 10.1371/journal.pone.0058611] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2012] [Accepted: 02/05/2013] [Indexed: 01/18/2023] Open
Abstract
Aims Alterations in properties of the bladder with maturation are relevant physiologically and pathophysiologically. The aim of this study was to investigate alterations in bladder properties with maturation in juvenile vs. adult pig, focussing on differences between layers of the bladder wall (mucosa vs. detrusor) and the presence and functional contribution of interstitial cells (ICs). Methods Basal and cholinergic-induced phasic contractions (PCs) in mucosal and denuded-detrusor strips from juvenile and adult pigs were assessed. Expression of c-kit, a marker of ICs, was investigated in the mucosa and the detrusor layers of the pig bladder. The functional role of ICs in mediating PCs was examined using imatinib. Results Mucosal strips from juvenile and adult pig bladders demonstrated basal PCs whilst denuded-detrusor strips did not. PCs of mucosal strips from juvenile pigs were significantly greater than those from adult bladders. Immunoreactivity for c-kit was detected in mucosa and detrusor layers of pig bladder. Histological studies demonstrated a distinct layer of smooth muscle between the urothelium and bladder detrusor, termed the muscularis mucosa. Imatinib was only effective in inhibiting PCs in mucosal strips from juvenile pigs. Imatinib inhibited the carbachol-induced PCs of both juvenile and adult denuded-detrusor strips, although strips from juvenile bladders demonstrated a trend towards being more sensitive to this inhibition. Conclusions We confirm the presence of c-kit positive ICs in pig urinary bladder. The enhanced PCs of mucosal strips from juvenile animals could be due to altered properties of ICs or the muscularis mucosa in the bladders of these animals.
Collapse
|
22
|
Induction of inflammatory cytokines and alteration of urothelial ATP, acetylcholine and prostaglandin E2 release by doxorubicin. Eur J Pharmacol 2012; 700:102-9. [PMID: 23219793 DOI: 10.1016/j.ejphar.2012.11.053] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2012] [Revised: 11/29/2012] [Accepted: 11/29/2012] [Indexed: 11/23/2022]
Abstract
Intravesical treatment with cytotoxic drugs such as doxorubicin is associated with local adverse effects in bladder cancer patients. Here we investigate the effects of doxorubicin on urothelial release of ATP, acetylcholine and prostaglandin E(2), and production of inflammatory cytokines. Urothelial cells were treated with doxorubicin for 1h at 37 °C. Immediately or 24 h following treatment the level of ATP, acetylcholine and prostaglandin E(2) released under basal and stimulated conditions was measured and compared to release from vehicle treated control cultures. The presence of inflammatory cytokines, in culture medium was also assessed 24 h after doxorubicin pre-treatment. Immediately following treatment, stimulated ATP release was inhibited at doxorubicin concentrations ≥1 μg/ml and showed partial recovery at 24 h. Immediately following treatment, basal acetylcholine release was increased by doxorubicin at its clinical concentration (1 mg/ml), while a concentration-dependent decrease in stimulated acetylcholine release was observed. Twenty four hour after treatment, basal acetylcholine release was increased in culture treated with 0.01 mg/ml doxorubicin while stimulated acetylcholine release remained depressed. A significant increase in prostaglandin E(2) release was observed in cells immediately and 24 h after treatment with doxorubicin. A 5.5- and 2-fold increase in interleukin -8 and -1β secretion, respectively was detected 24 h following doxorubicin treatment. These findings indicate that inflammatory cytokines interleukin-8 and -1β are induced and urothelial mediator release is affected by treatment with doxorubicin at clinically relevant concentrations and durations of treatment. These changes may play a role in the adverse effects associated with intravesical doxorubicin treatment.
Collapse
|
23
|
Birder LA, Ruggieri M, Takeda M, van Koeveringe G, Veltkamp S, Korstanje C, Parsons B, Fry CH. How does the urothelium affect bladder function in health and disease? ICI-RS 2011. Neurourol Urodyn 2012; 31:293-9. [PMID: 22275289 DOI: 10.1002/nau.22195] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2011] [Accepted: 12/06/2011] [Indexed: 11/11/2022]
Abstract
The urothelium is a multifunctional tissue that not only acts as a barrier between the vesical contents of the lower urinary tract and the underlying tissues but also acts as a sensory organ by transducing physical and chemical stresses to the attendant afferent nervous system and underlying smooth muscle. This review will consider the nature of the stresses that the urothelium can transduce; the transmitters that mediate the transduction process; and how lower urinary pathologies, including overactive bladder syndrome, painful bladder syndrome and bacterial infections, are associated with alterations to this sensory system. In particular, the role of muscarinic receptors and the TRPV channels system will be discussed in this context. The urothelium also influences the contractile state of detrusor smooth muscle, both through modifying its contractility and the extent of spontaneous activity; potential pathways are discussed. The potential role that the urothelium may play in bladder underactivity is introduced, as well as potential biomarkers for the condition that may cross the urothelium to the urine. Finally, consideration is given to vesical administration of therapeutic agents that influence urinary tract function and how the properties of the urothelium may determine the effectiveness of this mode of delivery.
Collapse
Affiliation(s)
- L A Birder
- Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.
| | | | | | | | | | | | | | | |
Collapse
|
24
|
Urothelial/Lamina Propria Spontaneous Activity and the Role of M3 Muscarinic Receptors in Mediating Rate Responses to Stretch and Carbachol. Urology 2011; 78:1442.e9-15. [DOI: 10.1016/j.urology.2011.08.039] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2011] [Revised: 07/10/2011] [Accepted: 08/18/2011] [Indexed: 11/22/2022]
|
25
|
ATP enhances spontaneous calcium activity in cultured suburothelial myofibroblasts of the human bladder. PLoS One 2011; 6:e25769. [PMID: 21998694 PMCID: PMC3187810 DOI: 10.1371/journal.pone.0025769] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2011] [Accepted: 09/11/2011] [Indexed: 11/19/2022] Open
Abstract
Background Suburothelial myofibroblasts (sMF) are located underneath the urothelium in close proximity to afferent nerves. They express purinergic receptors and show calcium transients in response to ATP. Therefore they are supposed to be involved in afferent signaling of the bladder fullness. Since ATP concentration is likely to be very low during the initial filling phase, we hypothesized that sMF Ca2+ activity is affected even at very low ATP concentrations. We investigated ATP induced modulation of spontaneous activity, intracellular calcium response and purinergic signaling in cultured sMF. Methodology/Principal Findings Myofibroblast cultures, established from cystectomies, were challenged by exogenous ATP in presence or absence of purinergic antagonist. Fura-2 calcium imaging was used to monitor ATP (10−16 to 10−4 mol/l) induced alterations of calcium activity. Purinergic receptors (P2X1, P2X2, P2X3) were analysed by confocal immunofluorescence. We found spontaneous calcium activity in 55.18%±1.65 of the sMF (N = 48 experiments). ATP significantly increased calcium activity even at 10−16 mol/l. The calcium transients were partially attenuated by subtype selective antagonist (TNP-ATP, 1 µM; A-317491, 1 µM), and were mimicked by the P2X1, P2X3 selective agonist α,β-methylene ATP. The expression of purinergic receptor subtypes in sMF was confirmed by immunofluorescence. Conclusions/Significance Our experiments demonstrate for the first time that ATP can modulate spontaneous activity and induce intracellular Ca2+ response in cultured sMF at very low concentrations, most likely involving P2X receptors. These findings support the notion that sMF are able to register bladder fullness very sensitively, which predestines them for the modulation of the afferent bladder signaling in normal and pathological conditions.
Collapse
|
26
|
Vahabi B, Lawson K, McKay NG, Sellers DJ. Phasic activity of urinary bladder smooth muscle in the streptozotocin-induced diabetic rat: effect of potassium channel modulators. Eur J Pharmacol 2011; 660:431-7. [PMID: 21497590 DOI: 10.1016/j.ejphar.2011.03.053] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2010] [Revised: 03/09/2011] [Accepted: 03/28/2011] [Indexed: 02/07/2023]
Abstract
Increased phasic activity in the bladder smooth muscle of animal models and patients with detrusor overactivity has been suggested to underlie the pathophysiology of overactive bladder. Potassium (K+) channels are key regulators of bladder smooth muscle tone and thus may play a role in this altered phasic activity. In this study the effects of K+ channel modulators on the phasic activity of bladder strips from the streptozotocin-induced diabetic rat model of bladder dysfunction were investigated. Bladder strips from rats 1 week following streptozotocin administration and age-matched controls were mounted in tissue baths at 37 °C and the effects of K+ channel modulators on resting basal tension or phasic activity induced by a low concentration of carbachol (0.5 μM) were investigated. Activation of BKCa channels by NS1619 had a minor inhibitory effect on carbachol-induced phasic activity of bladder strips from control and diabetic rats, and significantly inhibited amplitude only at 30 μM. Activation of KATP channels by cromakalim inhibited the frequency of carbachol-induced phasic activity of bladder strips, although strips from diabetic rats showed a trend towards being less sensitive to cromakalim. The BKCa channel blocker iberiotoxin was able to induce phasic activity in resting tissues, with diabetic bladder strips demonstrating significantly enhanced phasic activity compared to controls. In contrast, inhibition of SKCa and KATP channels did not induce phasic activity in resting tissues. In conclusion, responses of diabetic rat bladder to BKCa and KATP channel modulators are altered, suggesting altered function and/or expression of channels which may contribute to bladder dysfunction in this model.
Collapse
Affiliation(s)
- Bahareh Vahabi
- Biomedical Research Centre, Sheffield Hallam University, Howard Street, Sheffield S1 1WB, UK.
| | | | | | | |
Collapse
|
27
|
Cheng Y, Mansfield KJ, Sandow SL, Sadananda P, Burcher E, Moore KH. Porcine bladder urothelial, myofibroblast, and detrusor muscle cells: characterization and ATP release. Front Pharmacol 2011; 2:27. [PMID: 21713125 PMCID: PMC3113165 DOI: 10.3389/fphar.2011.00027] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2011] [Accepted: 05/23/2011] [Indexed: 12/15/2022] Open
Abstract
ATP is released from the bladder mucosa in response to stretch, but the cell types responsible are unclear. Our aim was to isolate and characterize individual populations of urothelial, myofibroblast, and detrusor muscle cells in culture, and to examine agonist-stimulated ATP release. Using female pig bladders, urothelial cells were isolated from bladder mucosa following trypsin-digestion of the luminal surface. The underlying myofibroblast layer was dissected, minced, digested, and cultured until confluent (10–14 days). A similar protocol was used for muscle cells. Cultures were used for immunocytochemical staining and/or ATP release investigations. In urothelial cultures, immunoreactivity was present for the cytokeratin marker AE1/AE3 but not the contractile protein α-smooth muscle actin (α-SMA) or the cytoskeletal filament vimentin. Neither myofibroblast nor muscle cell cultures stained for AE1/AE3. Myofibroblast cultures partially stained for α-SMA, whereas muscle cultures were 100% stained. Both myofibroblast and muscle stained for vimentin, however, they were morphologically distinct. Ultrastructural studies verified that the suburothelial layer of pig bladder contained abundant myofibroblasts, characterized by high densities of rough endoplasmic reticulum. Baseline ATP release was higher in urothelial and myofibroblast cultures, compared with muscle. ATP release was significantly stimulated by stretch in all three cell populations. Only urothelial cells released ATP in response to acid, and only muscle cells were stimulated by capsaicin. Tachykinins had no effect on ATP release. In conclusion, we have established a method for culture of three cell populations from porcine bladder, a well-known human bladder model, and shown that these are distinct morphologically, immunologically, and pharmacologically.
Collapse
Affiliation(s)
- Ying Cheng
- Detrusor Muscle Laboratory, St George Hospital, University of New South Wales Kogarah, NSW, Australia
| | | | | | | | | | | |
Collapse
|
28
|
Hidayat Santoso AG, Liang W. Bladder contractility is mediated by different K+ channels in the urothelium and detrusor smooth muscle. J Pharmacol Sci 2011; 115:127-134. [PMID: 21258177 DOI: 10.1254/jphs.10162fp] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2010] [Accepted: 11/03/2010] [Indexed: 10/18/2022] Open
Abstract
The roles played by K(+) channels in the urothelium (UE) and detrusor smooth muscle (DSM) in regulating agonist-induced bladder contraction is not known at present. Thus, the effects in carbachol (CCh)-induced contraction in UE-intact (+UE) and UE-denuded (-UE) rat detrusor strips pretreated with K(+)-channel blockers were investigated here. The K(+)-channel blockers used were 4-aminopyridine (4-AP), glibenclamide (Glib), iberiotoxin (IbTx), charybdotoxin (ChTx), and apamin. In the absence of K(+)-channel blockers, control CCh-induced contractions were more potent in -UE than +UE strips. Treatment with IbTx and apamin resulted in more potent CCh-induced contractions in +UE strips. In -UE strips, CCh potency was increased by ChTx and Glib, but decreased by 4-AP. Different K(+) channels in the UE and DSM were thus involved in regulating bladder contractions. Contractile mediatory function of these channels, specific to the UE or DSM, may be potential drug targets in the management of bladder disorders.
Collapse
|
29
|
Oger S, Behr-Roussel D, Gorny D, Bernabé J, Comperat E, Chartier-Kastler E, Denys P, Giuliano F. Effects of potassium channel modulators on myogenic spontaneous phasic contractile activity in human detrusor from neurogenic patients. BJU Int 2010; 108:604-11. [PMID: 21166758 DOI: 10.1111/j.1464-410x.2010.09935.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
OBJECTIVE To characterize the spontaneous contractile activity (SCA) developed by detrusor from patients with neurogenic detrusor overactivity (NDO) because the alteration of detrusor properties plays a critical role in the pathogenesis of detrusor overactivity, as well as to evaluate the role of K(ATP) and K(Ca) channels on this SCA because these channels regulate detrusor SCA in many species, including humans without overactive bladder (OAB). PATIENTS AND METHODS Human bladder samples were obtained from 44 patients undergoing cystectomy for bladder cancer with no known OAB symptoms and from 38 patients suffering from urodynamically diagnosed NDO. Detrusor strips with or without urothelium/suburothelium were mounted isometrically in organ baths filled with Krebs-HEPES (37 °C; 95% O(2) /5% CO(2) ). Strips were incubated with 10 µm pinacidil (K(ATP) opener) followed by 10 µm glibenclamide (K(ATP) blocker). In another set of experiments, strips were incubated with 30 µm NS-1619 (BK(Ca) opener) followed by 100 nm iberiotoxin (BK(Ca) blocker) or with 100 nm apamin (SK(Ca) blocker). RESULTS SCA occurred more frequently with larger amplitude and area under the curve in detrusor strips from NDO patients compared to control patients. The presence of urothelium/suburothelium did not significantly modify SCA in either patient population. Pinacidil markedly inhibited SCA of detrusor strips from control and NDO patients. This effect was reversed by glibenclamide. By contrast, NS-1619 followed by iberiotoxin did not elicit any significant changes in SCA from NDO patients, contrary to control patients. CONCLUSIONS K(ATP) and SK(Ca) channels regulate SCA of NDO patients' detrusor strips. By contrast, BK(Ca) channels are not involved in the regulation of detrusor SCA in NDO patients, whereas they regulate SCA in control patients. These results should be considered in the development of K(+) channels openers for the treatment of NDO. Moreover, SCA observed in vitro should be regarded as an in vitro modelling of human NDO.
Collapse
|
30
|
Ohmasa F, Saito M, Shimizu S, Taniguchi S, Dimitriadis F, Satoh I, Kinoshita Y, Satoh K. The role of ATP-sensitive potassium channel on acute urinary retention and subsequent catheterization in the rat. Eur J Pharmacol 2010; 635:194-7. [DOI: 10.1016/j.ejphar.2010.02.052] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2009] [Revised: 02/08/2010] [Accepted: 02/24/2010] [Indexed: 10/19/2022]
|
31
|
Saban R. Dual Contribution of Cyclooxygenase and Lipoxygenase Pathways in Bladder Contractility. J Urol 2009; 181:2416-7. [DOI: 10.1016/j.juro.2009.03.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Ricardo Saban
- Department of Physiology, College of Medicine, Oklahoma University Health Sciences Center, Oklahoma City, Oklahoma
| |
Collapse
|