1
|
Villa L, Weinhold P, Zaffuto E, Castiglione F, Pozzi E, Ventimiglia E, Buono R, Briganti A, Montorsi F, Salonia A, Hedlund P. The Rho-kinase inhibitor Y27632 promotes ureteral relaxation in an in vivo rat model for partial ureteral obstruction. World J Urol 2023; 41:2541-2547. [PMID: 37528287 DOI: 10.1007/s00345-023-04528-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2023] [Accepted: 07/07/2023] [Indexed: 08/03/2023] Open
Abstract
PURPOSE Aim of this study was to evaluate the effect of intravenous Y27632 (a ROK inhibitor) on intra-ureteral pressures and on blood pressure in an in vivo rat model for unilateral partial ureteral obstruction (PUO). METHODS 15 Male Sprague Dawley rats were used. Under isofluran anesthesia, saline was continuously infused via polyethylene (PE)-10 catheters inserted in the ureters beneath the kidney pelvis. Left psoas muscle was sutured around the distal left ureter to create a partial obstruction. Carotid artery and femoral vein were cannulated with PE catheters for registration of mean arterial blood pressure (MAP) and for administration of drugs. Left and right ureter pressures and MAP were simultaneously recorded. Y27632 (0.03 and 0.1 mg/kg each n = 6-7) was given intravenously. T-test was used for comparisons. RESULTS Spontaneous peristaltic pressure waves were recorded at baseline for both ureters. After the obstruction, Y27632 reduced maximum pressure (MaxP) by 10.5 ± 1.9% (0.03 mg/kg; p = 0.004) and 29.1 ± 4.8% (0.1 mg/kg; p < 0.001), minimum pressure (MinP) by 5.2 ± 2.3% (0.03 mg/kg; p = 0.02) and 12.2 ± 3.4% (0.1 mg/kg; p = 0.009), the area under the curve (AUC) by 7.8 ± 2.4% (0.03 mg/kg; p = 0.008) and 16.5 ± 3.7% (0.1 mg/kg;p = 0.007), the waves amplitude by 23.4 ± 11.3% (0.03 mg/kg; p = 0.098) and 38.7 ± 7.5% (0.1 mg/kg; p < 0.001), with no effect on contraction frequency. During simultaneous recordings from the normal ureter at the investigated doses, Y27632 reduced MaxP, MinP, AUC and waves amplitude by 1-7%. The MAP was reduced by 12.5 ± 5.3% (0.03 mg/kg; p = 0.07) and 15.8 ± 1.8% (0.1 mg/kg; p < 0.001). CONCLUSIONS Y27632 decreased intra-ureteral pressures of a partially obstructed ureter with limited effect on blood pressure in an animal model of unilateral PUO.
Collapse
Affiliation(s)
- Luca Villa
- Division of Experimental Oncology/Unit of Urology, URI, IRCCS Ospedale San Raffaele, Milan, Italy.
| | - Philipp Weinhold
- Department of Urology, Ludwig-Maximilians-University of Munich, Munich, Germany
| | | | | | - Edoardo Pozzi
- Division of Experimental Oncology/Unit of Urology, URI, IRCCS Ospedale San Raffaele, Milan, Italy
| | - Eugenio Ventimiglia
- Division of Experimental Oncology/Unit of Urology, URI, IRCCS Ospedale San Raffaele, Milan, Italy
| | - Roberta Buono
- Department of Molecular Biology and Biochemistry, University of California, Irvine, California, USA
| | - Alberto Briganti
- Division of Experimental Oncology/Unit of Urology, URI, IRCCS Ospedale San Raffaele, Milan, Italy
- University Vita-Salute San Raffaele, Milan, Italy
| | - Francesco Montorsi
- Division of Experimental Oncology/Unit of Urology, URI, IRCCS Ospedale San Raffaele, Milan, Italy
- University Vita-Salute San Raffaele, Milan, Italy
| | - Andrea Salonia
- Division of Experimental Oncology/Unit of Urology, URI, IRCCS Ospedale San Raffaele, Milan, Italy
- University Vita-Salute San Raffaele, Milan, Italy
| | - Petter Hedlund
- Department of Clinical Pharmacology, Linköping University, Linköping, Sweden
- Department of Experimental and Clinical Pharmacology, Lund University, Lund, Sweden
| |
Collapse
|
2
|
Excitation-Contraction Coupling in Ureteric Smooth Muscle: Mechanisms Driving Ureteric Peristalsis. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1124:103-119. [DOI: 10.1007/978-981-13-5895-1_4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
|
3
|
Lang RJ, Hashitani H. Pacemaker Mechanisms Driving Pyeloureteric Peristalsis: Modulatory Role of Interstitial Cells. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1124:77-101. [PMID: 31183823 DOI: 10.1007/978-981-13-5895-1_3] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
The peristaltic pressure waves in the renal pelvis that propel urine expressed by the kidney into the ureter towards the bladder have long been considered to be 'myogenic', being little affected by blockers of nerve conduction or autonomic neurotransmission, but sustained by the intrinsic release of prostaglandins and sensory neurotransmitters. In uni-papilla mammals, the funnel-shaped renal pelvis consists of a lumen-forming urothelium and a stromal layer enveloped by a plexus of 'typical' smooth muscle cells (TSMCs), in multi-papillae kidneys a number of minor and major calyces fuse into a large renal pelvis. Electron microscopic, electrophysiological and Ca2+ imaging studies have established that the pacemaker cells driving pyeloureteric peristalsis are likely to be morphologically distinct 'atypical' smooth muscle cells (ASMCs) that fire Ca2+ transients and spontaneous transient depolarizations (STDs) which trigger propagating nifedipine-sensitive action potentials and Ca2+ waves in the TSMC layer. In uni-calyceal kidneys, ASMCs predominately locate on the serosal surface of the proximal renal pelvis while in multi-papillae kidneys they locate within the sub-urothelial space. 'Fibroblast-like' interstitial cells (ICs) located in the sub-urothelial space or adventitia are a mixed population of cells, having regional and species-dependent expression of various Cl-, K+, Ca2+ and cationic channels. ICs display asynchronous Ca2+ transients that periodically synchronize into bursts that accelerate ASMC Ca2+ transient firing. This review presents current knowledge of the architecture of the proximal renal pelvis, the role Ca2+ plays in renal pelvis peristalsis and the mechanisms by which ICs may sustain/accelerate ASMC pacemaking.
Collapse
Affiliation(s)
- Richard J Lang
- School of Biomedical Sciences, Faculty of Medicine, Nursing and Health Sciences, Monash University, Clayton, VIC, Australia.
| | - Hikaru Hashitani
- Department of Cell Physiology, Graduate School of Medical Sciences, Nagoya City University, Nagoya, Japan
| |
Collapse
|
4
|
Sung TS, Lu H, Sung J, Yeom JH, Perrino BA, Koh SD. The functional role of protease-activated receptors on contractile responses by activation of Ca 2+ sensitization pathways in simian colonic muscles. Am J Physiol Gastrointest Liver Physiol 2018; 315:G921-G931. [PMID: 30260688 PMCID: PMC6336947 DOI: 10.1152/ajpgi.00255.2018] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
It has been known that activation of protease-activated receptors (PARs) affects gastrointestinal motility. In this study, we tested the effects of PAR agonists on electrical and contractile responses and Ca2+ sensitization pathways in simian colonic muscles. The Simian colonic muscle was initially hyperpolarized by PAR agonists. After the transient hyperpolarization, simian colonic muscle repolarized to the control resting membrane potential (RMP) without a delayed depolarization. Apamin significantly reduced the initial hyperpolarization, suggesting that activation of small conductance Ca2+-activated K+ (SK) channels is involved in the initial hyperpolarization. In contractile experiments, PAR agonists caused an initial relaxation followed by an increase in contractions. These delayed contractile responses were not matched with the electrical responses that showed no after depolarization of the RMP. To investigate the possible involvement of Rho-associated protein kinase 2 (ROCK) pathways in the PAR effects, muscle strips were treated with ROCK inhibitors, which significantly reduced the PAR agonist-induced contractions. Furthermore, PAR agonists increased MYPT1 phosphorylation, and ROCK inhibitors completely blocked MYPT1 phosphorylation. PAR agonists alone had no effect on CPI-17 phosphorylation. In the presence of apamin, PAR agonists significantly increased CPI-17 phosphorylation, which was blocked by protein kinase C (PKC) inhibitors suggesting that Ca2+ influx is increased by apamin and is activating PKC. In conclusion, these studies show that PAR activators induce biphasic responses in simian colonic muscles. The initial inhibitory responses by PAR agonists are mainly mediated by activation of SK channels and delayed contractile responses are mainly mediated by the CPI-17 and ROCK Ca2+ sensitization pathways in simian colonic muscles. NEW & NOTEWORTHY In the present study, we found that the contractile responses of simian colonic muscles to protease-activated receptor (PAR) agonists are different from the previously reported contractile responses of murine colonic muscles. Ca2+ sensitization pathways mediate the contractile responses of simian colonic muscles to PAR agonists without affecting the membrane potential. These findings emphasize novel mechanisms of PAR agonist-induced contractions possibly related to colonic dysmotility in inflammatory bowel disease.
Collapse
Affiliation(s)
- Tae Sik Sung
- 1Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada
| | - Hongli Lu
- 2Department of Physiology, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Juno Sung
- 1Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada
| | - Jong Hoon Yeom
- 3Department of Anesthesiology and Pain Medicine, Hanyang University, Seoul, Republic of Korea
| | - Brian A. Perrino
- 1Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada
| | - Sang Don Koh
- 1Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada
| |
Collapse
|
5
|
Lim I, Chess-Williams R, Sellers D. Altered ureteral contractility with ageing: Role of the rho-kinase pathway. Mech Ageing Dev 2018. [DOI: 10.1016/j.mad.2018.03.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
6
|
Nguyen M, Higashi R, Ohta K, Nakamura KI, Hashitani H, Lang R. Autonomic and sensory nerve modulation of peristalsis in the upper urinary tract. Auton Neurosci 2016; 200:1-10. [DOI: 10.1016/j.autneu.2015.07.425] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2014] [Revised: 07/20/2015] [Accepted: 07/28/2015] [Indexed: 11/24/2022]
|
7
|
Steinbach A, Schaper K, Koenen A, Schlüter T, Zimmermann U, Rettig R, Grisk O. Role of endothelin-1 for the regulation of renal pelvic function. Pflugers Arch 2016; 468:1467-78. [DOI: 10.1007/s00424-016-1848-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Revised: 05/17/2016] [Accepted: 06/06/2016] [Indexed: 10/21/2022]
|
8
|
Liu B, Lee YC, Alwaal A, Wang G, Banie L, Lin CS, Lin G, Lue TF. Carbachol-induced signaling through Thr696-phosphorylation of myosin phosphatase-targeting subunit 1 (MYPT1) in rat bladder smooth muscle cells. Int Urol Nephrol 2016; 48:1237-1242. [PMID: 27118568 DOI: 10.1007/s11255-016-1303-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2016] [Accepted: 04/19/2016] [Indexed: 12/18/2022]
Abstract
PURPOSE Lines of evidence suggest that Rho-associated protein kinase (ROCK)-mediated myosin phosphatase-targeting subunit 1 (MYPT1) phosphorylation plays a central role in smooth muscle contraction. However, the physiological significance of MYPT1 phosphorylation at Thr696 catalyzed by ROCK in bladder smooth muscle remains controversial. We attempt to directly observe the quantitative protein expression of Rho A/ROCK and phosphorylation of MYPT1 at Thr696 after carbachol administration in rat bladder smooth muscle cells (RBMSCs). MATERIALS AND METHODS Primary cultured smooth muscle cells were obtained from rat bladders. The effects of both concentration and time-course induced by the muscarinic agonist carbachol were investigated by assessing the expression of Rho A/ROCK and MYPT1 phosphorylation at Thr696 using Western blot. RESULTS In the dose-course studies, carbachol showed significant increase in phosphorylation of MYPT1 at Thr696 (p-MYPT1) from concentrations of 15-100 μM based on Western blot results (p < 0.05, ANOVA test). In the time-course studies, treatment of cells with 15 μM of carbachol significantly enhanced the expression of p-MYPT1 from 3 to 15 h (p < 0.05, ANOVA test) and induced the expression of Rho A from 10 to 120 min (p < 0.05, ANOVA test). CONCLUSIONS Carbachol can induce the expression of ROCK pathway, leading to MYPT1 phosphorylation at Thr696 and thereby sustained RBSMCs contraction.
Collapse
Affiliation(s)
- Benchun Liu
- Knuppe Molecular Urology Laboratory, Department of Urology, School of Medicine, University of California, 400 Parnassus Ave., Ste A-610, San Francisco, CA, 94143-0738, USA
| | - Yung-Chin Lee
- Knuppe Molecular Urology Laboratory, Department of Urology, School of Medicine, University of California, 400 Parnassus Ave., Ste A-610, San Francisco, CA, 94143-0738, USA
- Department of Urology, Faculty of Medicine, College of Medicine, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Amjad Alwaal
- Knuppe Molecular Urology Laboratory, Department of Urology, School of Medicine, University of California, 400 Parnassus Ave., Ste A-610, San Francisco, CA, 94143-0738, USA
| | - Guifang Wang
- Knuppe Molecular Urology Laboratory, Department of Urology, School of Medicine, University of California, 400 Parnassus Ave., Ste A-610, San Francisco, CA, 94143-0738, USA
| | - Lia Banie
- Knuppe Molecular Urology Laboratory, Department of Urology, School of Medicine, University of California, 400 Parnassus Ave., Ste A-610, San Francisco, CA, 94143-0738, USA
| | - Ching-Shwun Lin
- Knuppe Molecular Urology Laboratory, Department of Urology, School of Medicine, University of California, 400 Parnassus Ave., Ste A-610, San Francisco, CA, 94143-0738, USA
| | - Guiting Lin
- Knuppe Molecular Urology Laboratory, Department of Urology, School of Medicine, University of California, 400 Parnassus Ave., Ste A-610, San Francisco, CA, 94143-0738, USA
| | - Tom F Lue
- Knuppe Molecular Urology Laboratory, Department of Urology, School of Medicine, University of California, 400 Parnassus Ave., Ste A-610, San Francisco, CA, 94143-0738, USA.
| |
Collapse
|
9
|
Sutherland C, MacDonald JA, Walsh MP. Analysis of phosphorylation of the myosin-targeting subunit of myosin light chain phosphatase by Phos-tag SDS-PAGE. Am J Physiol Cell Physiol 2016; 310:C681-91. [PMID: 26864694 DOI: 10.1152/ajpcell.00327.2015] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2015] [Accepted: 02/08/2016] [Indexed: 01/28/2023]
Abstract
Phosphorylation of the myosin-targeting subunit 1 of myosin light chain phosphatase (MYPT1) plays an important role in the regulation of smooth muscle contraction, and several sites of phosphorylation by different protein Ser/Thr kinases have been identified. Furthermore, in some instances, phosphorylation at specific sites affects phosphorylation at neighboring sites, with functional consequences. Characterization of the complex phosphorylation of MYPT1 in tissue samples at rest and in response to contractile and relaxant stimuli is, therefore, challenging. We have exploited Phos-tag SDS-PAGE in combination with Western blotting using antibodies to MYPT1, including phosphospecific antibodies, to separate multiple phosphorylated MYPT1 species and quantify MYPT1 phosphorylation stoichiometry using purified, full-length recombinant MYPT1 phosphorylated by Rho-associated coiled-coil kinase (ROCK) and cAMP-dependent protein kinase (PKA). This approach confirmed that phosphorylation of MYPT1 by ROCK occurs at Thr(697)and Thr(855), PKA phosphorylates these two sites and the neighboring Ser(696)and Ser(854), and prior phosphorylation at Thr(697)and Thr(855)by ROCK precludes phosphorylation at Ser(696)and Ser(854)by PKA. Furthermore, phosphorylation at Thr(697)and Thr(855)by ROCK exposes two other sites of phosphorylation by PKA. Treatment of Triton-skinned rat caudal arterial smooth muscle strips with the membrane-impermeant phosphatase inhibitor microcystin or treatment of intact tissue with the membrane-permeant phosphatase inhibitor calyculin A induced slow, sustained contractions that correlated with phosphorylation of MYPT1 at 7 to ≥10 sites. Phos-tag SDS-PAGE thus provides a suitable and convenient method for analysis of the complex, multisite MYPT1 phosphorylation events involved in the regulation of myosin light chain phosphatase activity and smooth muscle contraction.
Collapse
Affiliation(s)
- Cindy Sutherland
- Department of Biochemistry and Molecular Biology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Justin A MacDonald
- Department of Biochemistry and Molecular Biology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Michael P Walsh
- Department of Biochemistry and Molecular Biology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| |
Collapse
|
10
|
Mills RD, Mita M, Walsh MP. A role for the Ca2+-dependent tyrosine kinase Pyk2 in tonic depolarization-induced vascular smooth muscle contraction. J Muscle Res Cell Motil 2015; 36:479-89. [DOI: 10.1007/s10974-015-9416-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2015] [Accepted: 06/27/2015] [Indexed: 10/24/2022]
|
11
|
Takeya K, Wang X, Sutherland C, Kathol I, Loutzenhiser K, Loutzenhiser RD, Walsh MP. Involvement of myosin regulatory light chain diphosphorylation in sustained vasoconstriction under pathophysiological conditions. J Smooth Muscle Res 2014; 50:18-28. [PMID: 24770446 PMCID: PMC5137258 DOI: 10.1540/jsmr.50.18] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Smooth muscle contraction is activated primarily by phosphorylation at Ser19 of the
regulatory light chain subunits (LC20) of myosin II, catalysed by
Ca2+/calmodulin-dependent myosin light chain kinase.
Ca2+-independent contraction can be induced by inhibition of myosin light chain
phosphatase, which correlates with diphosphorylation of LC20 at Ser19 and
Thr18, catalysed by integrin-linked kinase (ILK) and zipper-interacting protein kinase
(ZIPK). LC20 diphosphorylation at Ser19 and Thr18 has been detected in
mammalian vascular smooth muscle tissues in response to specific contractile stimuli (e.g.
endothelin-1 stimulation of rat renal afferent arterioles) and in pathophysiological
situations associated with hypercontractility (e.g. cerebral vasospasm following
subarachnoid hemorrhage). Comparison of the effects of LC20 monophosphorylation
at Ser19 and diphosphorylation at Ser19 and Thr18 on contraction and relaxation of
Triton-skinned rat caudal arterial smooth muscle revealed that phosphorylation at Thr18
has no effect on steady-state force induced by Ser19 phosphorylation. On the other hand,
the rates of dephosphorylation and relaxation are significantly slower following
diphosphorylation at Thr18 and Ser19 compared to monophosphorylation at Ser19. We propose
that this diphosphorylation mechanism underlies the prolonged contractile response of
particular vascular smooth muscle tissues to specific stimuli, e.g. endothelin-1
stimulation of renal afferent arterioles, and the vasospastic behavior observed in
pathological conditions such as cerebral vasospasm following subarachnoid hemorrhage and
coronary arterial vasospasm. ILK and ZIPK may, therefore, be useful therapeutic targets
for the treatment of such conditions.
Collapse
Affiliation(s)
- Kosuke Takeya
- Department of Physiology, Asahikawa Medical College, Hokkaido, Japan
| | | | | | | | | | | | | |
Collapse
|
12
|
Wallace HL, Southern KW, Connell MG, Wray S, Burdyga T. Abnormal tracheal smooth muscle function in the CF mouse. Physiol Rep 2013; 1:e00138. [PMID: 24400140 PMCID: PMC3871453 DOI: 10.1002/phy2.138] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2013] [Revised: 10/03/2013] [Accepted: 10/04/2013] [Indexed: 12/29/2022] Open
Abstract
Increased airway smooth muscle (ASM) contractility is thought to underlie symptoms of airway hyperresponsiveness (AHR). In the cystic fibrosis (CF) airway, ASM anomalies have been reported, but have not been fully characterized and the underlying mechanisms are largely unknown. We examined ASM in an adult CF mouse tracheal ring preparation, and determined whether changes in contractility were associated with altered ASM morphology. We looked for inherent changes in the cellular pathways involved in contractility, and characterized trachea morphology in the adult trachea and in an embryonic lung culture model during development. Results showed that that there was a reduction in tracheal caliber in CF mice as indicated by a reduction in the number of cartilage rings; proximal cross-sectional areas of cftr (-/-) tracheas and luminal areas were significantly smaller, but there was no difference in the area or distribution of smooth muscle. Morphological differences observed in adult trachea were not evident in the embryonic lung at 11.5 days gestation or after 72 h in culture. Functional data showed a significant reduction in the amplitude and duration of contraction in response to carbachol (CCh) in Ca-free conditions. The reduction in contraction was agonist specific, and occurred throughout the length of the trachea. These data show that there is a loss in the contractile capacity of the CF mouse trachea due to downregulation of the pathway specific to acetylcholine (ACh) activation. This reduction in contraction is not associated with changes in the area or distribution of ASM.
Collapse
Affiliation(s)
- Helen L Wallace
- Department of Cellular and Molecular Physiology, Institute of Translational Medicine, University of Liverpool Liverpool, U.K
| | - Kevin W Southern
- Department for Women's and Children's Health, Institute of Translational Medicine, University of Liverpool Liverpool, U.K
| | - Marilyn G Connell
- Department for Women's and Children's Health, Institute of Translational Medicine, University of Liverpool Liverpool, U.K
| | - Susan Wray
- Department of Cellular and Molecular Physiology, Institute of Translational Medicine, University of Liverpool Liverpool, U.K
| | - Theodor Burdyga
- Department of Cellular and Molecular Physiology, Institute of Translational Medicine, University of Liverpool Liverpool, U.K
| |
Collapse
|
13
|
Bhetwal BP, Sanders KM, An C, Trappanese DM, Moreland RS, Perrino BA. Ca2+ sensitization pathways accessed by cholinergic neurotransmission in the murine gastric fundus. J Physiol 2013; 591:2971-86. [PMID: 23613531 DOI: 10.1113/jphysiol.2013.255745] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Ca(2+) sensitization of contraction has typically been investigated by bathing muscles in solutions containing agonists. However, it is unknown whether bath-applied agonists and enteric neurotransmission activate similar Ca(2+) sensitization mechanisms. We investigated protein kinase C (PKC)-potentiated phosphatase inhibitor protein of 17 kDa (CPI-17) and myosin phosphatase targeting subunit 1 (MYPT1) phosphorylation in murine gastric fundus muscles stimulated by bath-applied carbachol (CCh) or cholinergic motor neurotransmission. CCh increased MYPT1 phosphorylation at Thr696 (pT696) and Thr853 (pT853), CPI-17 at Thr38 (pT38), and myosin light chain at Ser19 (pS19). Electrical field stimulation (EFS) only increased pT38. In the presence of neostigmine, EFS increased pT38, pT853 and pS19. In fundus muscles of W/W(v) mice, EFS alone increased pT38 and pT853. Atropine blocked all contractions and all increases in pT696, pT853, pT38 and pS19. The Rho kinase (ROCK) inhibitor SAR1x blocked increases in pT853 and pT696. The PKC inhibitors Go6976 and Gf109203x or nicardipine blocked increases in pT38 and pT696. These findings suggest that cholinergic motor neurotransmission activates PKC-dependent CPI-17 phosphorylation. Bath-applied CCh recruits additional ROCK-dependent MYPT1 phosphorylation due to exposure of the agonist to a wider population of muscarinic receptors. Intramuscular interstitial cells of Cajal (ICC-IMs) and cholinesterases restrict ACh accessibility to a select population of muscarinic receptors, possibly only those expressed by ICC-IMs. These results provide the first biochemical evidence for focalized (or synaptic-like) neurotransmission, rather than diffuse 'volume' neurotransmission in a smooth muscle tissue. Furthermore, these findings demonstrate that bath application of contractile agonists to gastrointestinal smooth muscles does not mimic physiological responses to cholinergic neurotransmission.
Collapse
Affiliation(s)
- Bhupal P Bhetwal
- University of Nevada School of Medicine, Physiology and Cell Biology, University of Nevada, Reno, CMM203E, Reno, NV 89557, USA
| | | | | | | | | | | |
Collapse
|
14
|
Lee WC, Chiang PH, Tain YL, Wu CC, Chuang YC. Sensory dysfunction of bladder mucosa and bladder oversensitivity in a rat model of metabolic syndrome. PLoS One 2012; 7:e45578. [PMID: 23029112 PMCID: PMC3446912 DOI: 10.1371/journal.pone.0045578] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2012] [Accepted: 08/22/2012] [Indexed: 01/21/2023] Open
Abstract
Purpose To study the role of sensory dysfunction of bladder mucosa in bladder oversensitivity of rats with metabolic syndrome. Materials and Methods Female Wistar rats were fed a fructose-rich diet (60%) or a normal diet for 3 months. Based on cystometry, the fructose-fed rats (FFRs) were divided into a group with normal detrusor function or detrusor overactivity (DO). Acidic adenosine triphosphate (ATP) solution (5mM, pH 3.3) was used to elicit reflex micturition. Cystometric parameters were evaluated before and after drug administration. Functional proteins of the bladder mucosa were assessed by western blotting. Results Compared to the controls, intravesical acidic ATP solution instillation induced a significant increase in provoked phasic contractions in both FFR groups and a significant decrease in the mean functional bladder capacity of group DO. Pretreatment with capsaicin for C-fiber desentization, intravesical liposome for mucosal protection, or intravenous pyridoxal 5-phosphate 6-azophenyl-2′,4′-disulfonic acid for antagonized purinergic receptors can interfere with the urodynamic effects of intravesical ATP in FFRs and controls. Over-expression of TRPV1, P2X3, and iNOS proteins, and down-regulation of eNOS proteins were observed in the bladder mucosa of both fructose-fed groups. Conclusions Alterations of sensory receptors and enzymes in the bladder mucosa, including over-expression of TRPV1, P2X3, and iNOS proteins, can precipitate the emergence of bladder phasic contractions and oversensitivity through the activation of C-afferents during acidic ATP solution stimulation in FFRs. The down-regulation of eNOS protein in the bladder mucosa of FFRs may lead to a failure to suppress bladder oversensitivity and phasic contractions. Sensory dysfunction of bladder mucosa and DO causing by metabolic syndrome are easier to elicit bladder oversensitivity to certain urothelium stimuli.
Collapse
Affiliation(s)
- Wei-Chia Lee
- Division of Urology, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - Po-Hui Chiang
- Division of Urology, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - You-Lin Tain
- Department of pediatrics, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - Chia-Ching Wu
- Department of International Business, College of Commerce and Management, Cheng Shiu University, Kaohsiung, Taiwan
| | - Yao-Chi Chuang
- Division of Urology, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan
- * E-mail:
| |
Collapse
|
15
|
Grassie ME, Sutherland C, Ulke-Lemée A, Chappellaz M, Kiss E, Walsh MP, MacDonald JA. Cross-talk between Rho-associated kinase and cyclic nucleotide-dependent kinase signaling pathways in the regulation of smooth muscle myosin light chain phosphatase. J Biol Chem 2012; 287:36356-69. [PMID: 22948155 DOI: 10.1074/jbc.m112.398479] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Ca(2+) sensitization of smooth muscle contraction depends upon the activities of protein kinases, including Rho-associated kinase, that phosphorylate the myosin phosphatase targeting subunit (MYPT1) at Thr(697) and/or Thr(855) (rat sequence numbering) to inhibit phosphatase activity and increase contractile force. Both Thr residues are preceded by the sequence RRS, and it has been suggested that phosphorylation at Ser(696) prevents phosphorylation at Thr(697). However, the effects of Ser(854) and dual Ser(696)-Thr(697) and Ser(854)-Thr(855) phosphorylations on myosin phosphatase activity and contraction are unknown. We characterized a suite of MYPT1 proteins and phosphospecific antibodies for specificity toward monophosphorylation events (Ser(696), Thr(697), Ser(854), and Thr(855)), Ser phosphorylation events (Ser(696)/Ser(854)) and dual Ser/Thr phosphorylation events (Ser(696)-Thr(697) and Ser(854)-Thr(855)). Dual phosphorylation at Ser(696)-Thr(697) and Ser(854)-Thr(855) by cyclic nucleotide-dependent protein kinases had no effect on myosin phosphatase activity, whereas phosphorylation at Thr(697) and Thr(855) by Rho-associated kinase inhibited phosphatase activity and prevented phosphorylation by cAMP-dependent protein kinase at the neighboring Ser residues. Forskolin induced phosphorylation at Ser(696), Thr(697), Ser(854), and Thr(855) in rat caudal artery, whereas U46619 induced Thr(697) and Thr(855) phosphorylation and prevented the Ser phosphorylation induced by forskolin. Furthermore, pretreatment with forskolin prevented U46619-induced Thr phosphorylations. We conclude that cross-talk between cyclic nucleotide and RhoA signaling pathways dictates the phosphorylation status of the Ser(696)-Thr(697) and Ser(854)-Thr(855) inhibitory regions of MYPT1 in situ, thereby regulating the activity of myosin phosphatase and contraction.
Collapse
Affiliation(s)
- Michael E Grassie
- Smooth Muscle Research Group and Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, Alberta T2N 4Z6, Canada
| | | | | | | | | | | | | |
Collapse
|