Isoprostanes evoke contraction of the murine and human detrusor muscle via activation of the thromboxane prostanoid TP receptor and Rho-kinase

2021 ◽  
Author(s):  
Péter József Molnár ◽  
Bálint Dér ◽  
Kinga Borsodi ◽  
Helga Balla ◽  
Zsófia Borbás ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Urinary Bladder ◽  
Detrusor Overactivity ◽  
Ex Vivo ◽  
Purinergic Receptor ◽  
Rho Kinase ◽  
Disulfonic Acid ◽  
Detrusor Muscle ◽  
Tp Receptor ◽  
Dose Dependent

Local or systemic inflammation can severely impair urinary bladder functions and contribute to the development of voiding disorders in millions of people worldwide. Isoprostanes are inflammatory lipid mediators that are upregulated in the blood and urine by oxidative stress and may potentially induce detrusor overactivity. The aim of the study was to investigate the effects and signal transduction of isoprostanes in human and murine urinary bladders to provide potential pharmacological targets in detrusor overactivity. Contraction force was measured with myograph in murine and human urinary bladder smooth muscle (UBSM) ex vivo. Isoprostane 8-iso-PGE2 and 8-iso-PGF2α evoked dose-dependent contraction in murine UBSM, which was abolished in mice deficient for the thromboxane prostanoid receptor (TP-KO). The responses remained unaltered after removal of the mucosa or incubation with tetrodotoxin. Smooth muscle specific deletion of Gα12/13-protein or inhibition of Rho-kinase (ROCK) by Y-27632 decreased the contractions. In Gαq/11‐KO mice, responses were reduced and in the presence of Y‐27632 abolished completely. In human UBSM the TP agonist U-46619 evoked dose‐dependent contractions. Neither atropine, nor the purinergic receptor antagonist pyridoxalphosphate‐6‐azophenyl‐2',4'‐disulfonic acid (PPADS) decreased the effect, indicating that TP receptors directly mediate detrusor muscle contraction. 8-iso-PGE2 and 8-iso-PGF2α evoked dose-dependent contraction in human UBSM, and these responses were abolished by the TP antagonist SQ-29548 and were decreased by Y-27632. Our results indicate that isoprostanes evoke contraction in murine and human UBs, an effect mediated by the TP receptor. The G12/13-Rho-ROCK pathway plays a significant role in mediating the contraction and therefore may be a potential therapeutic target.

scholarly journals Nerve transfer for restoration of lower motor neuron-lesioned bladder function. Part 2: Attenuation of purinergic bladder smooth muscle contractions.

2021 ◽  
Author(s):  
Nagat Frara ◽  
Dania Giaddui ◽  
Alan S Braverman ◽  
Danielle S. Porreca ◽  
Justin M Brown ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Ex Vivo ◽  
Purinergic Receptor ◽  
Muscle Contractions ◽  
Bladder Function ◽  
Detrusor Muscle ◽  
Bladder Smooth Muscle ◽  
Contractile Responses ◽  
Smooth Muscle Contractions

This study determined the effect of pelvic organ decentralization and reinnervation one year later on the contribution of muscarinic and purinergic receptors to ex-vivo, nerve-evoked, bladder smooth muscle contractions. Nineteen canines underwent decentralization by bilateral transection of all coccygeal and sacral (S) spinal roots, dorsal roots of lumbar (L)7 and hypogastric nerves. After exclusions, 8 were reinnervated 12 months post-decentralization with obturator-to-pelvic and sciatic-to-pudendal nerve transfers then euthanized 8-12 months later; four served as long-term decentralized only animals. Controls included six sham-operated and three unoperated animals. Detrusor muscle was assessed for contractile responses to potassium chloride (KCl) and electric field stimulation (EFS) before and after purinergic receptor desensitization with alpha, beta-methylene adenosine triphosphate (α,β-mATP), muscarinic receptor antagonism with atropine, or sodium channel blockade with tetrodotoxin. Atropine inhibition of EFS-induced contractions increased in decentralized and reinnervated animals compared to controls. Maximal contractile responses to α,β-mATP did not differ between groups. In strips from decentralized and reinnervated animals, the contractile response to EFS was enhanced at lower frequencies compared to normal controls. The observation of increased blockade of nerve-evoked contractions by muscarinic antagonist with no change in responsiveness to purinergic agonist suggests either decreased ATP release or increased ecto-ATPase activity in detrusor muscle as a consequence of the long-term decentralization. The reduction in the frequency required to produce maximum contraction following decentralization may be due to enhanced nerve sensitivity to EFS or a change in the effectiveness of the neurotransmission.

scholarly journals Expression and functional role of Rho-kinase in rat urinary bladder smooth muscle

2003 ◽  
Vol 138 (5) ◽  
pp. 757-766 ◽  
Author(s):  
Alexandra Wibberley ◽  
Zunxuan Chen ◽  
Erding Hu ◽  
J Paul Hieble ◽  
Timothy D Westfall
Keyword(s):  
Smooth Muscle ◽  
Urinary Bladder ◽  
Functional Role ◽  
Rho Kinase ◽  
Bladder Smooth Muscle ◽  
Rat Urinary Bladder ◽  
Urinary Bladder Smooth Muscle

scholarly journals NK2 receptor-mediated detrusor muscle contraction involves Gq/11-dependent activation of voltage-dependent Ca2+ channels and the RhoA-Rho kinase pathway

2019 ◽  
Vol 317 (5) ◽  
pp. F1154-F1163 ◽  
Author(s):  
Bálint Dér ◽  
Péter József Molnár ◽  
Éva Ruisanchez ◽  
Petra Őrsy ◽  
Margit Kerék ◽  
...  
Keyword(s):  
Urinary Bladder ◽  
Rho Kinase ◽  
Detrusor Muscle ◽  
Dependent Manner ◽  
Contraction Force ◽  
Rhoa Activity ◽  
Voltage Dependent ◽  
Intracellular Ca ◽  
Nk2 Receptor ◽  
Kinase Pathway

Tachykinins (TKs) are involved in both the physiological regulation of urinary bladder functions and development of overactive bladder syndrome. The aim of the present study was to investigate the signal transduction pathways of TKs in the detrusor muscle to provide potential pharmacological targets for the treatment of bladder dysfunctions related to enhanced TK production. Contraction force, intracellular Ca2+ concentration, and RhoA activity were measured in the mouse urinary bladder smooth muscle (UBSM). TKs and the NK2 receptor (NK2R)-specific agonist [β-Ala8]-NKA(4–10) evoked contraction, which was inhibited by the NKR2 antagonist MEN10376. In Gαq/11-deficient mice, [β-Ala8]-NKA(4–10)-induced contraction and the intracellular Ca2+ concentration increase were abolished. Although Gq/11 proteins are linked principally to phospholipase Cβ and inositol trisphosphate-mediated Ca2+ release from intracellular stores, we found that phospholipase Cβ inhibition and sarcoplasmic reticulum Ca2+ depletion failed to have any effect on contraction induced by [β-Ala8]-NKA(4–10). In contrast, lack of extracellular Ca2+ or blockade of voltage-dependent Ca2+ channels (VDCCs) suppressed contraction. Furthermore, [β-Ala8]-NKA(4–10) increased RhoA activity in the UBSM in a Gq/11-dependent manner and inhibition of Rho kinase with Y-27632 decreased contraction force, whereas the combination of Y-27632 with either VDCC blockade or depletion of extracellular Ca2+ resulted in complete inhibition of [β-Ala8]-NKA(4–10)-induced contractions. In summary, our results indicate that NK2Rs are linked exclusively to Gq/11 proteins in the UBSM and that the intracellular signaling involves the simultaneous activation of VDCC and the RhoA-Rho kinase pathway. These findings may help to identify potential therapeutic targets of bladder dysfunctions related to upregulation of TKs.

scholarly journals Injectable Gel Form of a Decellularized Bladder Induces Adipose-Derived Stem Cell Differentiation into Smooth Muscle Cells In Vitro

2020 ◽  
Vol 21 (22) ◽  
pp. 8608
Author(s):  
Victoria Moreno-Manzano ◽  
Daria Zaytseva-Zotova ◽  
Eric López-Mocholí ◽  
Álvaro Briz-Redón ◽  
Berit Løkensgard Strand ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Urinary Bladder ◽  
Smooth Muscle Cells ◽  
Stem Cell Differentiation ◽  
Muscle Cells ◽  
Enzymatic Digestion ◽  
Biological Properties ◽  
Detrusor Muscle ◽  
Extracellular Matrix Components

Biologic scaffolds composed of extracellular matrix components have been proposed to repair and reconstruct a variety of tissues in clinical and pre-clinical studies. Injectable gels can fill and conform any three-dimensional shape and can be delivered to sites of interest by minimally invasive techniques. In this study, a biological gel was produced from a decellularized porcine urinary bladder by enzymatic digestion with pepsin. The enzymatic digestion was confirmed by visual inspection after dissolution in phosphate-buffered saline solution and Fourier-transform infrared spectroscopy. The rheological and biological properties of the gel were characterized and compared to those of the MatrigelTM chosen as a reference material. The storage modulus G’ reached 19.4 ± 3.7 Pa for the 30 mg/mL digested decellularized bladder gels after ca. 3 h at 37 °C. The results show that the gel formed of the porcine urinary bladder favored the spontaneous differentiation of human and rabbit adipose-derived stem cells in vitro into smooth muscle cells to the detriment of cell proliferation. The results support the potential of the developed injectable gel for tissue engineering applications to reconstruct for instance the detrusor muscle part of the human urinary bladder.

scholarly journals Nerve transfer for restoration of lower motor neuron-lesioned bladder function. Part 3: Correlation between histological changes and nerve evoked contractions

2021 ◽  
Author(s):  
Mary F Barbe ◽  
Courtney L Testa ◽  
Geneva E. Cruz ◽  
Nagat Frara ◽  
Ekta Tiwari ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Contractile Function ◽  
Ex Vivo ◽  
Bladder Function ◽  
Detrusor Muscle ◽  
Axon Density ◽  
Spinal Roots ◽  
One Year ◽  
Intramural Ganglia ◽  
Stimulation Of

We determined the effect of pelvic organ decentralization and reinnervation one year later on urinary bladder histology and function. Nineteen canines underwent decentralization by bilateral transection of all coccygeal and sacral (S) spinal roots, dorsal roots of lumbar (L)7 and hypogastric nerves. After exclusions, 8 were reinnervated 12 months post-decentralization with obturator-to-pelvic and sciatic-to-pudendal nerve transfers, then euthanized 8-12 months later; four served as long-term decentralized only animals. Before euthanasia, pelvic or transferred nerves and L1-S3 spinal roots were stimulated and maximum detrusor pressure (MDP) recorded. Bladder specimens were collected for histological and ex vivo smooth muscle contractility studies. Both reinnervated and decentralized animals showed less or denuded urothelium, fewer intramural ganglia, and more inflammation and collagen, than controls, although percent muscle was maintained. In reinnervated animals, pgp9.5+ axon density was higher, compared to decentralized animals. Ex vivo smooth muscle contractions in response to KCl correlated positively with submucosal inflammation, detrusor muscle thickness, pgp9.5+ axon density. In vivo, reinnervated animals showed higher MDP after stimulation of L1-L6 roots, compared to their transected L7-S3 roots, and reinnervated and decentralized animals showed lower MDP than controls after stimulation of nerves (due likely to fibrotic nerve encapsulation). MDP correlated negatively with detrusor collagen and inflammation, and positively with pgp9.5+ axon density and intramural ganglia numbers. These results demonstrate that bladder function can be improved by transfer of obturator nerves to pelvic nerves at one year after decentralization, although the fibrosis and inflammation that developed were associated with decreased contractile function.

scholarly journals Frequency encoding of cholinergic- and purinergic-mediated signaling to mouse urinary bladder smooth muscle: modulation by BK channels

2007 ◽  
Vol 292 (1) ◽  
pp. R616-R624 ◽  
Author(s):  
Matthias E. Werner ◽  
Anna-Maria Knorn ◽  
Andrea L. Meredith ◽  
Richard W. Aldrich ◽  
Mark T. Nelson
Keyword(s):  
Smooth Muscle ◽  
Urinary Bladder ◽  
Bk Channels ◽  
Bk Channel ◽  
Detrusor Muscle ◽  
Wild Type ◽  
Bladder Smooth Muscle ◽  
Overactive Detrusor ◽  
Maximal Force ◽  
Urinary Bladder Smooth Muscle

In the urinary bladder, contractions of the detrusor muscle and urine voiding are induced by the neurotransmitters ACh and ATP, released from parasympathetic nerves. Activation of K+ channels, in particular the large-conductance Ca2+-activated K+ (BK) channels, opposes increases in excitability and contractility of urinary bladder smooth muscle (UBSM). We have shown that deleting the gene mSlo1 in mice ( Slo−/−), encoding the BK channel, leads to enhanced nerve-mediated and neurotransmitter-dependent contractility of UBSM ( 38 ). Here, we examine the location of the BK channel in urinary bladder strips from mouse. Immunohistochemical analysis revealed that the channel is expressed in UBSM but not in nerves that innervate the smooth muscle. The relationship between electrical field stimulation and force generation of the cholinergic and purinergic pathways was examined by applying blockers of the respective receptors in UBSM strips from wild-type and from Slo−/− (knockout) mice. In wild-type strips, the stimulation frequency required to obtain a half-maximal force was significantly lower for the purinergic (7.2 ± 0.3 Hz) than the cholinergic pathway (19.1 ± 1.5 Hz), whereas the maximum force was similar. Blocking BK channels with iberiotoxin or ablation of the Slo gene increased cholinergic- and purinergic-mediated force at low frequencies, i.e., significantly decreased the frequency for a half-maximal force. Our results indicate that the BK channel has a very significant role in reducing both cholinergic- and purinergic-induced contractility and suggest that alterations in BK channel expression or function could contribute to pathologies such as overactive detrusor.

Ex vivo deformations of the urinary bladder wall during whole bladder filling: Contributions of extracellular matrix and smooth muscle

2010 ◽  
Vol 43 (9) ◽  
pp. 1708-1716 ◽  
Author(s):  
Aron Parekh ◽  
Alexander D. Cigan ◽  
Silvia Wognum ◽  
Rebecca L. Heise ◽  
Michael B. Chancellor ◽  
...  
Keyword(s):  
Extracellular Matrix ◽  
Smooth Muscle ◽  
Urinary Bladder ◽  
Ex Vivo ◽  
Bladder Wall ◽  
Bladder Filling ◽  
Urinary Bladder Wall

Involvement of Ca2+Sensitization in Ropivacaine-induced Contraction of Rat Aortic Smooth Muscle

2005 ◽  
Vol 103 (3) ◽  
pp. 548-555 ◽  
Author(s):  
Jingui Yu ◽  
Yasuyuki Tokinaga ◽  
Toshiyuki Kuriyama ◽  
Nobuhiko Uematsu ◽  
Kazuhiro Mizumoto ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Protein Kinase ◽  
Rho Kinase ◽  
Mapk Signaling ◽  
Mitogen Activated Protein Kinase ◽  
Dependent Manner ◽  
Membrane Translocation ◽  
Aortic Smooth Muscle ◽  
Calphostin C ◽  
Dose Dependent

Background The mechanisms of amino-amide local anesthetic agent-induced vasoconstriction remain unclear. The current study was designed to examine the roles of the protein kinase C (PKC), Rho kinase, and p44/42 mitogen-activated protein kinase (p44/42 MAPK) signaling pathways in calcium (Ca2+)-sensitization mechanisms in ropivacaine-induced vascular contraction. Methods Endothelium-denuded rat aortic rings, segments, and strips were prepared. The cumulative dose-response relations of contraction and intracellular Ca2+ concentration to ropivacaine were tested, using isometric force transducers and a fluorometer, respectively. The dose-dependent ropivacaine-induced phosphorylation of PKC and p44/42 MAPK and the membrane translocation of Rho kinase were also detected using Western blotting. Results Ropivacaine induced a dose-dependent biphasic contractile response and an increase in intracellular Ca2+ concentration of rat aortic rings, increasing at concentrations of 3 x 10 m to 3 x 10 m and decreasing from 10 m to 3 x 10 m, with a greater tension/intracellular Ca2+ concentration ratio than that induced with potassium chloride. The contraction was attenuated in a dose-dependent manner, by the PKC inhibitors bisindolylmaleimide I and calphostin C, the Rho-kinase inhibitor Y 27632, and the p44/42 MAPK inhibitor PD 098059. Ropivacaine also induced an increase in phosphorylation of PKC and p44/42 MAPK, and membrane translocation of Rho kinase in accordance with the contractile responses, which were also significantly inhibited by bisindolylmaleimide I and calphostin C, Y 27632, and PD 098059, correspondingly. Conclusion These findings demonstrated that PKC-, Rho kinase-, and p44/42 MAPK-mediated Ca2+-sensitization mechanisms are involved in the ropivacaine-induced biphasic contraction of rat aortic smooth muscle.

scholarly journals Transient contractions of urinary bladder smooth muscle are drivers of afferent nerve activity during filling

2016 ◽  
Vol 147 (4) ◽  
pp. 323-335 ◽  
Author(s):  
Thomas J. Heppner ◽  
Nathan R. Tykocki ◽  
David Hill-Eubanks ◽  
Mark T. Nelson
Keyword(s):  
Smooth Muscle ◽  
Urinary Bladder ◽  
Sensory Nerve ◽  
Bk Channels ◽  
Filling Pressure ◽  
Afferent Nerve ◽  
Detrusor Muscle ◽  
Afferent Activity ◽  
Intravesical Pressure ◽  
Nerve Activity

Activation of afferent nerves during urinary bladder (UB) filling conveys the sensation of UB fullness to the central nervous system (CNS). Although this sensory outflow is presumed to reflect graded increases in pressure associated with filling, UBs also exhibit nonvoiding, transient contractions (TCs) that cause small, rapid increases in intravesical pressure. Here, using an ex vivo mouse bladder preparation, we explored the relative contributions of filling pressure and TC-induced pressure transients to sensory nerve stimulation. Continuous UB filling caused an increase in afferent nerve activity composed of a graded increase in baseline activity and activity associated with increases in intravesical pressure produced by TCs. For each ∼4-mmHg pressure increase, filling pressure increased baseline afferent activity by ∼60 action potentials per second. In contrast, a similar pressure elevation induced by a TC evoked an ∼10-fold greater increase in afferent activity. Filling pressure did not affect TC frequency but did increase the TC rate of rise, reflecting a change in the length-tension relationship of detrusor smooth muscle. The frequency of afferent bursts depended on the TC rate of rise and peaked before maximum pressure. Inhibition of small- and large-conductance Ca2+-activated K+ (SK and BK) channels increased TC amplitude and afferent nerve activity. After inhibiting detrusor muscle contractility, simulating the waveform of a TC by gently compressing the bladder evoked similar increases in afferent activity. Notably, afferent activity elicited by simulated TCs was augmented by SK channel inhibition. Our results show that afferent nerve activity evoked by TCs represents the majority of afferent outflow conveyed to the CNS during UB filling and suggest that the maximum TC rate of rise corresponds to an optimal length-tension relationship for efficient UB contraction. Furthermore, our findings implicate SK channels in controlling the gain of sensory outflow independent of UB contractility.

5-Oxo-ETE regulates tone of guinea pig airway smooth muscle via activation of Ca2+ pools and Rho-kinase pathway

2004 ◽  
Vol 287 (4) ◽  
pp. L631-L640 ◽  
Author(s):  
Frederic Mercier ◽  
Caroline Morin ◽  
Martin Cloutier ◽  
Sonia Proteau ◽  
Joshua Rokach ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Guinea Pig ◽  
Airway Smooth Muscle ◽  
Kinase Inhibitor ◽  
Rho Kinase ◽  
Eicosatetraenoic Acid ◽  
Chlorobenzoic Acid ◽  
Tp Receptor ◽  
Lower Amplitude ◽  
Inotropic Responses

5-Oxo-6,8,11,14-eicosatetraenoic acid (5-oxo-ETE) is a proinflammatory mediator, but its effects on airway smooth muscle (ASM) have never been assessed. Tension measurements performed on guinea pig ASM showed that 5-oxo-ETE induced sustained concentration-dependent positive inotropic responses (EC50 = 0.89 μM) of somewhat lower amplitude than those induced by carbamylcholine and the thromboxane A2 (TXA2) agonist U-46619. Transient inotropic responses to 5-oxo-ETE were recorded in Ca2+-free medium, suggesting mobilization of intracellular Ca2+. Meanwhile, the sustained contraction, which required Ca2+ entry, was partially blocked by 1 μM nifedipine (an L-type Ca2+ channel blocker) but relatively insensitive to 100 μM Gd3+. The 5-oxo-ETE responses were also inhibited by indomethacin and SC-560 [a cyclooxygenase (COX-1) inhibitor] pretreatments but not by NS-398 (a selective COX-2 inhibitor). The contractile effects of 5-oxo-ETE on ASM were inhibited by the selective TXA2 receptor (TP receptor) antagonist SQ-29548 (−75%) and by 2-(p-amylcinnamoyl) amino-4-chlorobenzoic acid pretreatment, a phospholipase A2 inhibitor (−66%), suggesting that the major part of its effect is mediated by the release of TXA2. ASM responses to 5-oxo-ETE were also blocked by the Rho-kinase inhibitor Y-27632, which also partially inhibited the response to the TP receptor agonist U-46619, suggesting that the contractile response is due in part to Ca2+ sensitization of ASM cell myofilaments.

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