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Dhaese I, Lefebvre RA. Myosin light chain phosphatase activation is involved in the hydrogen sulfide-induced relaxation in mouse gastric fundus. Eur J Pharmacol 2009; 606:180-6. [PMID: 19374871 DOI: 10.1016/j.ejphar.2009.01.011] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2008] [Revised: 11/24/2008] [Accepted: 01/09/2009] [Indexed: 01/09/2023]
Abstract
The relaxant effect of hydrogen sulfide (H(2)S) in the vascular tree is well established but its influence and mechanism of action in gastrointestinal smooth muscle was hardly investigated. The influence of H(2)S on contractility in mouse gastric fundus was therefore examined. Sodium hydrogen sulfide (NaHS; H(2)S donor) was administered to prostaglandin F(2alpha) (PGF(2alpha))-contracted circular muscle strips of mouse gastric fundus, before and after incubation with interfering drugs. NaHS caused a concentration-dependent relaxation of the pre-contracted mouse gastric fundus strips. The K(+) channels blockers glibenclamide, apamin, charybdotoxin, 4-aminopyridin and barium chloride had no influence on the NaHS-induced relaxation. The relaxation by NaHS was also not influenced by L-NAME, ODQ and SQ 22536, inhibitors of the cGMP and cAMP pathway, by nerve blockers capsazepine, omega-conotoxin and tetrodotoxin or by several channel and receptor blockers (ouabain, nifedipine, 2-aminoethyl diphenylborinate, ryanodine and thapsigargin). The myosin light chain phosphatase (MLCP) inhibitor calyculin-A reduced the NaHS-induced relaxation, but the Rho-kinase inhibitor Y-27632 had no influence. We show that NaHS is able to relax PGF(2alpha)-contracted mouse gastric fundus strips. The results suggest that in the mouse gastric fundus, H(2)S causes relaxation at least partially via activation of MLCP.
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Affiliation(s)
- Ingeborg Dhaese
- Heymans Institute of Pharmacology, Ghent University, Ghent, Belgium
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2
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Lei Y, Cao YX, Xu CB, Zhang Y. The Raf-1 inhibitor GW5074 and dexamethasone suppress sidestream smoke-induced airway hyperresponsiveness in mice. Respir Res 2008; 9:71. [PMID: 18976506 PMCID: PMC2599896 DOI: 10.1186/1465-9921-9-71] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2008] [Accepted: 11/03/2008] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Sidestream smoke is closely associated with airway inflammation and hyperreactivity. The present study was designed to investigate if the Raf-1 inhibitor GW5074 and the anti-inflammatory drug dexamethasone suppress airway hyperreactivity in a mouse model of sidestream smoke exposure. METHODS Mice were repeatedly exposed to smoke from four cigarettes each day for four weeks. After the first week of the smoke exposure, the mice received either dexamethasone intraperitoneally every other day or GW5074 intraperitoneally every day for three weeks. The tone of the tracheal ring segments was recorded with a myograph system and concentration-response curves were obtained by cumulative administration of agonists. Histopathology was examined by light microscopy. RESULTS Four weeks of exposure to cigarette smoke significantly increased the mouse airway contractile response to carbachol, endothelin-1 and potassium. Intraperitoneal administration of GW5074 or dexamethasone significantly suppressed the enhanced airway contractile responses, while airway epithelium-dependent relaxation was not affected. In addition, the smoke-induced infiltration of inflammatory cells and mucous gland hypertrophy were attenuated by the administration of GW5074 or dexamethasone. CONCLUSION Sidestream smoke induces airway contractile hyperresponsiveness. Inhibition of Raf-1 activity and airway inflammation suppresses smoking-associated airway hyperresponsiveness.
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Affiliation(s)
- Ying Lei
- Department of Pharmacology, Xi'an Jiaotong University College of Medicine, No. 76, Yanta West Road, Xi'an, Shaanxi Province 710061, PR China
| | - Yong-Xiao Cao
- Department of Pharmacology, Xi'an Jiaotong University College of Medicine, No. 76, Yanta West Road, Xi'an, Shaanxi Province 710061, PR China
| | - Cang-Bao Xu
- Division of Experimental Vascular Research, Institute of Clinical Science in Lund, Lund University, Lund, Sweden
| | - Yaping Zhang
- Division of Experimental Vascular Research, Institute of Clinical Science in Lund, Lund University, Lund, Sweden
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3
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Sausbier M, Zhou XB, Beier C, Sausbier U, Wolpers D, Maget S, Martin C, Dietrich A, Ressmeyer AR, Renz H, Schlossmann J, Hofmann F, Neuhuber W, Gudermann T, Uhlig S, Korth M, Ruth P. Reduced rather than enhanced cholinergic airway constriction in mice with ablation of the large conductance Ca2+-activated K+ channel. FASEB J 2006; 21:812-22. [PMID: 17197382 DOI: 10.1096/fj.06-7167com] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The unique voltage- and Ca2+-dependent K+ (BK) channel, prominently expressed in airway smooth muscle cells, has been suggested as an important effector in controlling airway contractility. Its deletion in mice depolarized resting membrane potential of tracheal cells, suggesting an increased open-probability of voltage-gated Ca2+ channels. While carbachol concentration-dependently increased the tonic tension of wild-type (WT) trachea, mutant trachea showed a different response with rapid tension development followed by phasic contractions superimposed on a tonic component. Tonic contractions were substantially more dependent on L-type Ca2+ current in mutant than in WT trachea, even though L-type Ca2+ channels were not up-regulated. In the absence of L-type Ca2+ current, half-maximal contraction of trachea was shifted from 0.51 to 1.7 microM. In agreement, cholinergic bronchoconstriction was reduced in mutant lung slices, isolated-perfused lungs and, most impressively, in mutant mice analyzed by body plethysmography. Furthermore, isoprenaline-mediated airway relaxation was enhanced in mutants. In-depth analysis of cAMP and cGMP signaling revealed up-regulation of the cGMP pathway in mutant tracheal muscle. Inhibition of cGMP kinase reestablished normal sensitivity toward carbachol, indicating that up-regulation of cGMP signaling counterbalances for BK channel ablation, pointing to a predominant role of BK channel in regulation of airway tone.
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Affiliation(s)
- Matthias Sausbier
- Pharmakologie und Toxikologie, Pharmazeutisches Institut, Universität Tübingen, Tübingen, Germany
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4
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Hirota S, Pertens E, Janssen LJ. The reverse mode of the Na(+)/Ca(2+) exchanger provides a source of Ca(2+) for store refilling following agonist-induced Ca(2+) mobilization. Am J Physiol Lung Cell Mol Physiol 2006; 292:L438-47. [PMID: 17041014 DOI: 10.1152/ajplung.00222.2006] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Agonist-induced contraction of airway smooth muscle (ASM) can be triggered by an elevation in the intracellular Ca(2+) concentration, primarily through the release of Ca(2+) from the sarcoplasmic reticulum (SR). The refilling of the SR is integral for subsequent contractions. It has been suggested that Ca(2+) entry via store-operated cation (SOC) and receptor-operated cation channels may facilitate refilling of the SR. Indeed, depletion of the SR activates substantial inward SOC currents in ASM that are composed of both Ca(2+) and Na(+). Accumulation of Na(+) within the cell may regulate Ca(2+) handling in ASM by forcing the Na(+)/Ca(2+) exchanger (NCX) into the reverse mode, leading to the influx of Ca(2+) from the extracellular domain. Since depletion of the SR activates substantial inward Na(+) current, it is conceivable that the reverse mode of the NCX may contribute to the intracellular Ca(2+) pool from which the SR is refilled. Indeed, successive contractions of bovine ASM, evoked by various agonists (ACh, histamine, 5-HT, caffeine) were significantly reduced upon removal of extracellular Na(+); whereas contractions evoked by KCl were unchanged by Na(+) depletion. Ouabain, a selective inhibitor of the Na(+)/K(+) pump, had no effect on the reductions observed under normal and zero-Na(+) conditions. KB-R7943, a selective inhibitor of the reverse mode of the NCX, significantly reduced successive contractions induced by all agonists without altering KCl responses. Furthermore, KB-R7943 abolished successive caffeine-induced Ca(2+) transients in single ASM cells. Together, these data suggest a role for the reverse mode of the NCX in refilling the SR in ASM following Ca(2+) mobilization.
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Affiliation(s)
- Simon Hirota
- Asthma Research Group, Firestone Institute for Respiratory Health, St. Joseph's Healthcare, and Department of Medicine, McMaster University, Hamilton, Ontario, Canada
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5
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Bai Y, Zhang M, Sanderson MJ. Contractility and Ca2+ signaling of smooth muscle cells in different generations of mouse airways. Am J Respir Cell Mol Biol 2006; 36:122-30. [PMID: 16931808 PMCID: PMC1899303 DOI: 10.1165/rcmb.2006-0036oc] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
The control and mechanisms of airway smooth muscle cell (SMC) contraction were investigated with a sequential series of lung slices from different generations of the same airway from the cardiac lobe of the mouse lung. Airway contraction was measured by monitoring the changes in airway lumen area with phase-contrast microscopy. Changes in intracellular calcium concentration of the SMCs were studied with a custom-built confocal or two-photon microscope. The distribution of the airway SMCs and the muscarinic M(3) or 5-HT(2A) receptors was determined with immunofluorescence. Methacholine and 5-HT induced a concentration-dependent airway contraction and Ca(2+) oscillations within the SMCs of each airway generation. The airway contraction in response to the same agonist concentration was greater in the middle generation compared with the distal or proximal generations of the same airway. Similarly, the Ca(2+) oscillations varied in different generations of the same airway, with a slower frequency in the SMCs of the distal zone as compared with the middle or proximal zones of airways. By contrast, high KCl induced minimal contraction and very slow Ca(2+) oscillations throughout the whole intrapulmonary airway. The slower agonist-induced Ca(2+) oscillations in the distal zone correlated with a reduced expression of agonist receptors. The layer of SMCs increased in thickness in the middle and proximal zones. These results indicate that the contractility of airway SMCs varies at different positions along the same airway and that this response partially results from different Ca(2+) signaling and the total amount of the SMCs.
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Affiliation(s)
- Yan Bai
- Department of Physiology, University of Massachusetts Medical School, Worcester, MA 01655, USA
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6
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van Meijeren CE, Vleeming W, van de Kuil T, Manni J, Kegler D, Hendriksen CFM, de Wildt DJ. In vivo pertussis toxin treatment reduces contraction of rat resistance arteries but not that of mouse trachea. Eur J Pharmacol 2004; 488:127-35. [PMID: 15044044 DOI: 10.1016/j.ejphar.2004.02.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2003] [Revised: 01/26/2004] [Accepted: 02/03/2004] [Indexed: 11/26/2022]
Abstract
In order to develop an in vitro method for detecting residual pertussis toxin activity in acellular pertussis vaccines, the effects of in vivo pertussis toxin treatment on contraction and relaxation properties of isolated mouse trachea and of isolated rat small mesenteric resistance arteries were studied. In vivo pertussis toxin treatment (24 or 72 microg/kg, intraperitoneally (i.p.)) did not affect contraction and relaxation properties of isolated BALB/c or NIH mouse trachea. In vivo pertussis toxin treatment (30 microg/kg, intravenously) significantly reduced noradrenaline- or KCl-induced maximal contraction and reduced sensitivity to noradrenaline in isolated male Wistar rat small mesenteric resistance arteries. However, in vivo pertussis toxin treatment did not affect relaxation properties of isolated rat small mesenteric resistance arteries. These results support the hypothesis that vasoconstriction-regulating mechanisms and not airway constriction mechanisms are involved in pertussis toxin-induced histamine sensitisation. The vasoconstriction-regulating mechanisms may provide a lead for further development of an in vitro method for measuring biologically active pertussis toxin in acellular pertussis vaccines based on mechanisms involved in the histamine sensitisation test.
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Affiliation(s)
- Cornelia E van Meijeren
- National Institute for Public Health and Environment, Laboratory of Toxicology, Pathology and Genetics, P.O. Box 1, 3720 BA Bilthoven, The Netherlands.
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7
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Walker JKL, Gainetdinov RR, Feldman DS, McFawn PK, Caron MG, Lefkowitz RJ, Premont RT, Fisher JT. G protein-coupled receptor kinase 5 regulates airway responses induced by muscarinic receptor activation. Am J Physiol Lung Cell Mol Physiol 2003; 286:L312-9. [PMID: 14565944 DOI: 10.1152/ajplung.00255.2003] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
G protein-coupled receptors (GPCRs) transduce extracellular signals into intracellular events. The waning responsiveness of GPCRs in the face of persistent agonist stimulation, or desensitization, is a necessary event that ensures physiological homeostasis. GPCR kinases (GRKs) are important regulators of GPCR desensitization. GRK5, one member of the GRK family, desensitizes central M(2) muscarinic receptors in mice. We questioned whether GRK5 might also be an important regulator of peripheral muscarinic receptor responsiveness in the cardiopulmonary system. Specifically, we wanted to determine the role of GRK5 in regulating muscarinic receptor-mediated control of airway smooth muscle tone or regulation of cholinergic-induced bradycardia. Tracheal pressure, heart rate, and tracheal smooth muscle tension were measured in mice having a targeted deletion of the GRK5 gene (GRK5(-/-)) and littermate wild-type (WT) control mice. Both in vivo and in vitro results showed that the airway contractile response to a muscarinic receptor agonist was not different between GRK5(-/-) and WT mice. However, the relaxation component of bilateral vagal stimulation and the airway smooth muscle relaxation resulting from beta(2)-adrenergic receptor activation were diminished in GRK5(-/-) mice. These data suggest that M(2) muscarinic receptor-mediated opposition of airway smooth muscle relaxation is regulated by GRK5 and is, therefore, excessive in GRK5(-/-) mice. In addition, this study shows that GRK5 regulates pulmonary responses in a tissue- and receptor-specific manner but does not regulate peripheral cardiac muscarinic receptors. GRK5 regulation of airway responses may have implications in obstructive airway diseases such as asthma or chronic obstructive pulmonary disease.
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Affiliation(s)
- J K L Walker
- Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA.
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Adner M, Rose AC, Zhang Y, Swärd K, Benson M, Uddman R, Shankley NP, Cardell LO. An assay to evaluate the long-term effects of inflammatory mediators on murine airway smooth muscle: evidence that TNFalpha up-regulates 5-HT(2A)-mediated contraction. Br J Pharmacol 2002; 137:971-82. [PMID: 12429569 PMCID: PMC1573572 DOI: 10.1038/sj.bjp.0704928] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2002] [Revised: 08/06/2002] [Accepted: 08/16/2002] [Indexed: 11/09/2022] Open
Abstract
1. Asthma research is arguably limited by an absence of appropriate animal models to study the pharmacology of inflammatory mediators that affect airway hyperresponsiveness and remodelling. Here we assessed an assay based on mouse tracheal segments cultured for 1-32 days, and investigated contractile responses mediated by muscarinic and 5-hydroxytryptamine (5-HT) receptors following long-term exposure to tumour necrosis factor-alpha (TNFalpha). 2. Following culture, in the absence of TNFalpha, maximum contractile responses to KCl and carbachol were similar, with an increase in response up to day two and a decrease to a stable level after 8 days. Maximal relaxations to isoprenaline were not affected by the culture procedure. The potency of KCl and isoprenaline increased throughout the study. DNA microarray data revealed that global gene expression changes were greater when tissues were introduced to culture than when they were maintained in culture. The morphology of smooth muscle cells was maintained throughout the culture period. 3. 5-HT induced a weak contraction in both fresh and cultured (up to 8 days) segments. Culture with TNFalpha produced a time- and concentration-dependent increase in the maximal contraction to 5-HT, evidently mediated by 5-HT(2A) receptors, whereas, the potency for carbachol was reduced. 4. In conclusion, the phenotype of airway smooth muscle remained largely intact during the culture period, even though minor changes were obtained during the first days of culture. The time-dependent effect of TNFalpha indicates the importance of studying the long-term effect of cytokines on the smooth muscle cells in relation to airway hyperresponsiveness and remodelling.
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Affiliation(s)
- Mikael Adner
- Department of Otorhinolaryngology, Malmö University Hospital, SE-20502 Malmö, Sweden.
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9
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Yang Q, Yim APC, Arifi AA, He GW. Procaine in cardioplegia: the effect on EDHF-mediated function in porcine coronary arteries. J Card Surg 2002; 17:470-5. [PMID: 12630551 DOI: 10.1111/j.1540-8191.2001.tb01180.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVES Hyperkalemia in cardioplegia impairs the endothelium-derived hyperpolarizing factor (EDHF)-mediated function. This study examined the effect of procaine in cardioplegia on the EDHF-mediated response in porcine coronary arteries. METHODS An isometric force study was performed in a myograph. Two rings taken from the same artery (diameter 200-450 microm) were incubated with Krebs solution (group I) or 20 mM K+ (group II) with/without procaine (1 mM) at 37 degrees C for 1 hour. The EDHF-mediated relaxation was induced by bradykinin (BK, -10 approximately -6.5 log M) after U46619 (-8 log M, in group I) or K+-precontraction (in group II) in the presence of indomethacin (7 microM), NG-nitro-L-arginine (300 microM), and hemoglobin (20 microM). The membrane potential of a single smooth muscle cell was measured by a microelectrode after superfusion with Krebs solution with/without procaine for 1 hour. RESULTS The EDHF-mediated relaxation was increased by the treatment with procaine with the EC50 shifted leftward (97.3 +/- 0.6% vs. 83.0 +/- 5.1% at -7 log M and 99.4 +/- 0.6% vs. 96.7 +/- 1.6% at -6.5 log M, p < 0.05; EC50: -8.57 +/- 0.24 vs. -7.92 +/- 0.23 log M, p < 0.05). Procaine decreased the BK-induced hyperpolarization from -72.3 +/- 0.7 mV to -68.8 +/- 0.8 mV (-6.5 log M, p < 0.01). The EDHF-mediated relaxation in arteries exposed to 20 mM K+ was not altered by procaine (49.9 +/- 7.4% vs. 55.8 +/- 7.6%, p > 0.05). CONCLUSIONS In the coronary arteries, procaine has a depolarizing effect but it enhances EDHF-mediated relaxation. Addition of procaine in cardioplegia did not change the EDHF-mediated endothelial function.
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Affiliation(s)
- Qin Yang
- Division of Cardiothoracic Surgery, Department of Surgery, The Chinese University of Hong Kong, Hong Kong SAR, China
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10
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van Lunteren E, Moyer M. Auxotonic contractile responses of rat tracheal and bronchial airway smooth muscle. Pulm Pharmacol Ther 2002; 14:443-53. [PMID: 11782124 DOI: 10.1006/pupt.2001.0308] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The purposes of the present study were to directly compare: (1) the degree of trachealis muscle shortening and changes in tracheal dimensions and (2) ACh-mediated auxotonic contraction of trachea and intraparenchymal bronchi. The auxotonic contractile properties of tracheal and bronchial airway smooth muscle were assessed from 1-2 mm thick tracheal sections and;1 mm thick lung slices using videomicrometry in vitro at 37 degrees C. Acetylcholine resulted in reductions in luminal area, perimeter, mean radius, length, and breadth (22.0, 10.0, 11.9, 10.7 and 12.0%, respectively). Trachealis muscle shortening reached a maximum of 39.8+/-4.3%. The K(+)channel blocker 4-aminopyridine significantly augmented the ACh-mediated reductions in tracheal luminal dimensions. In response to ACh (10(-3)m), reductions in bronchial dimensions were significantly greater than those of the trachea for luminal area, perimeter and mean radius (44.6 vs. 18.6, 32.0 vs. 8.0 and 28.9 vs. 9.9%, respectively). These data indicate that auxotonic contractile responses of rat tracheal smooth muscle differ from those previously reported in the dog and guinea pig, that ACh-mediated auxotonic contraction of tracheal smooth muscle is augmented by 4-aminopyridine, and that proportionate reductions in luminal dimensions in response to ACh are considerably greater for bronchial than tracheal airways.
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Affiliation(s)
- E van Lunteren
- Case Western Reserve University and Louis Stokes Cleveland Department of Veteran Affairs Medical Center, Cleveland, OH 44106-1782, USA.
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Nakahara T, Moriuchi H, Yunoki M, Kubota Y, Tanaka Y, Sakamato K, Shigenobu K, Ishii K. Involvement of K(+) channel in procainamide-induced relaxation of bovine tracheal smooth muscle. Eur J Pharmacol 2000; 402:143-9. [PMID: 10940368 DOI: 10.1016/s0014-2999(00)00467-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The relaxant effect of procainamide, a class Ia antiarrhythmic agent, was examined in bovine tracheal smooth muscle. Procainamide produced concentration-dependent decreases in tension and full relaxation in the preparations contracted with methacholine (0.3 microM). By comparison, in preparations contracted with 40 mM K(+), procainamide had only slight relaxant effects. The relaxant effects of cromakalim and salbutamol on 40 mM K(+)-contracted preparations were significantly (P<0.01) smaller than those on 0.3 microM methacholine-contracted ones. On the other hand, the concentration-response relationships for quinidine, lidocaine, mexiletine and propafenone were not so dramatically different between 0.3 microM methacholine- and 40 mM K(+)-contracted preparations. Tetraethylammonium (300 microM), iberiotoxin (30 nM) and Ba(2+) (1 mM) significantly (P<0.05) attenuated the relaxant effects of procainamide on methacholine-induced contractions, whereas apamin (100 nM), 4-aminopyridine (300 microM), and glibenclamide (10 microM) did not affect them. The inhibitory effect of a combination of iberiotoxin and Ba(2+) was greater than that of iberiotoxin or Ba(2+) alone (P<0.01). These results suggest that the activation of at least two types of K(+) (maxi-K(+) and inward rectifier K(+)) channels contributes to the procainamide-induced relaxation of bovine tracheal smooth muscle.
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Affiliation(s)
- T Nakahara
- Department of Molecular Pharmacology, Kitasato University School of Pharmaceutical Sciences, 5-9-1 Shirokane, Minato-ku, Tokyo 108-8641, Japan.
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