Abstract
Sensory nerves play an important role in airway disease by mediating central reflexes such as cough, and local axon reflexes resulting in the peripheral release of neuropeptides. We have tested whether the benzimidazolone compound, NS1619, an opener of large conductance calcium-activated potassium (BK Ca) channels, inhibits the activity of sensory fibers, and central and local airway reflexes in guinea pig airways. In in vitro single fiber recording experiments, NS1619 applied to identified receptive fields in the trachea inhibited the firing of A(delta)-fibers evoked by hypertonic saline and distilled water, and bradykinin-evoked firing of C-fibers. Electrically evoked nonadrenergic noncholinergic contractions of isolated bronchi mediated by the release of neurokinin A (NKA) from C-fibers, but not those elicited by exogenous NKA, were inhibited by NS1619. These effects of NS1619 were prevented by iberiotoxin, a selective blocker of BK Ca channels. In conscious guinea pigs, cough evoked by aerosolized citric acid was also inhibited by NS1619. These data show that BK Ca channel activation inhibits sensory nerve activity, resulting in a reduction of both afferent and efferent function. BK Ca channel openers may therefore be of potential benefit in reducing neurogenic inflammation and central reflexes seen during inflammatory conditions of the airways, and may represent a new class of antitussive drug.
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Selected References
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- Barnes P. J., Baraniuk J. N., Belvisi M. G. Neuropeptides in the respiratory tract. Part I. Am Rev Respir Dis. 1991 Nov;144(5):1187–1198. doi: 10.1164/ajrccm/144.5.1187. [DOI] [PubMed] [Google Scholar]
- Belvisi M. G., Chung K. F., Jackson D. M., Barnes P. J. Opioid modulation of non-cholinergic neural bronchoconstriction in guinea-pig in vivo. Br J Pharmacol. 1988 Oct;95(2):413–418. doi: 10.1111/j.1476-5381.1988.tb11661.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Belvisi M. G., Ichinose M., Barnes P. J. Modulation of non-adrenergic, non-cholinergic neural bronchoconstriction in guinea-pig airways via GABAB-receptors. Br J Pharmacol. 1989 Aug;97(4):1225–1231. doi: 10.1111/j.1476-5381.1989.tb12582.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Candia S., Garcia M. L., Latorre R. Mode of action of iberiotoxin, a potent blocker of the large conductance Ca(2+)-activated K+ channel. Biophys J. 1992 Aug;63(2):583–590. doi: 10.1016/S0006-3495(92)81630-2. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Choudry N. B., Fuller R. W., Pride N. B. Sensitivity of the human cough reflex: effect of inflammatory mediators prostaglandin E2, bradykinin, and histamine. Am Rev Respir Dis. 1989 Jul;140(1):137–141. doi: 10.1164/ajrccm/140.1.137. [DOI] [PubMed] [Google Scholar]
- Choudry N. B., Fuller R. W. Sensitivity of the cough reflex in patients with chronic cough. Eur Respir J. 1992 Mar;5(3):296–300. [PubMed] [Google Scholar]
- Coleridge H. M., Coleridge J. C., Ginzel K. H., Baker D. G., Banzett R. B., Morrison M. A. Stimulation of 'irritant' receptors and afferent C-fibres in the lungs by prostaglandins. Nature. 1976 Dec 2;264(5585):451–453. doi: 10.1038/264451a0. [DOI] [PubMed] [Google Scholar]
- Coleridge H. M., Coleridge J. C. Pulmonary reflexes: neural mechanisms of pulmonary defense. Annu Rev Physiol. 1994;56:69–91. doi: 10.1146/annurev.ph.56.030194.000441. [DOI] [PubMed] [Google Scholar]
- Coleridge J. C., Coleridge H. M. Afferent vagal C fibre innervation of the lungs and airways and its functional significance. Rev Physiol Biochem Pharmacol. 1984;99:1–110. doi: 10.1007/BFb0027715. [DOI] [PubMed] [Google Scholar]
- Edwards G., Niederste-Hollenberg A., Schneider J., Noack T., Weston A. H. Ion channel modulation by NS 1619, the putative BKCa channel opener, in vascular smooth muscle. Br J Pharmacol. 1994 Dec;113(4):1538–1547. doi: 10.1111/j.1476-5381.1994.tb17171.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Empey D. W., Laitinen L. A., Jacobs L., Gold W. M., Nadel J. A. Mechanisms of bronchial hyperreactivity in normal subjects after upper respiratory tract infection. Am Rev Respir Dis. 1976 Feb;113(2):131–139. doi: 10.1164/arrd.1976.113.2.131. [DOI] [PubMed] [Google Scholar]
- Eschenbacher W. L., Boushey H. A., Sheppard D. Alteration in osmolarity of inhaled aerosols cause bronchoconstriction and cough, but absence of a permeant anion causes cough alone. Am Rev Respir Dis. 1984 Feb;129(2):211–215. [PubMed] [Google Scholar]
- Fox A. J., Barnes P. J., Dray A. Stimulation of guinea-pig tracheal afferent fibres by non-isosmotic and low-chloride stimuli and the effect of frusemide. J Physiol. 1995 Jan 1;482(Pt 1):179–187. doi: 10.1113/jphysiol.1995.sp020508. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Fox A. J., Barnes P. J., Urban L., Dray A. An in vitro study of the properties of single vagal afferents innervating guinea-pig airways. J Physiol. 1993 Sep;469:21–35. doi: 10.1113/jphysiol.1993.sp019802. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Fox A. J., Lalloo U. G., Belvisi M. G., Bernareggi M., Chung K. F., Barnes P. J. Bradykinin-evoked sensitization of airway sensory nerves: a mechanism for ACE-inhibitor cough. Nat Med. 1996 Jul;2(7):814–817. doi: 10.1038/nm0796-814. [DOI] [PubMed] [Google Scholar]
- Fox A. J., Urban L., Barnes P. J., Dray A. Effects of capsazepine against capsaicin- and proton-evoked excitation of single airway C-fibres and vagus nerve from the guinea-pig. Neuroscience. 1995 Aug;67(3):741–752. doi: 10.1016/0306-4522(95)00115-y. [DOI] [PubMed] [Google Scholar]
- Fuller R. W., Dixon C. M., Cuss F. M., Barnes P. J. Bradykinin-induced bronchoconstriction in humans. Mode of action. Am Rev Respir Dis. 1987 Jan;135(1):176–180. doi: 10.1164/arrd.1987.135.1.176. [DOI] [PubMed] [Google Scholar]
- Grundemar L., Grundström N., Johansson I. G., Andersson R. G., Håkanson R. Suppression by neuropeptide Y of capsaicin-sensitive sensory nerve-mediated contraction in guinea-pig airways. Br J Pharmacol. 1990 Mar;99(3):473–476. doi: 10.1111/j.1476-5381.1990.tb12952.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Grundström N., Andersson R. G., Wikberg J. E. Inhibition of the excitatory non-adrenergic, non-cholinergic neurotransmission in the guinea pig tracheo-bronchial tree mediated by alpha 2-adrenoceptors. Acta Pharmacol Toxicol (Copenh) 1984 Jan;54(1):8–14. doi: 10.1111/j.1600-0773.1984.tb01889.x. [DOI] [PubMed] [Google Scholar]
- Holland M., Langton P. D., Standen N. B., Boyle J. P. Effects of the BKCa channel activator, NS1619, on rat cerebral artery smooth muscle. Br J Pharmacol. 1996 Jan;117(1):119–129. doi: 10.1111/j.1476-5381.1996.tb15163.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Ichinose M., Barnes P. J. A potassium channel activator modulates both excitatory noncholinergic and cholinergic neurotransmission in guinea pig airways. J Pharmacol Exp Ther. 1990 Mar;252(3):1207–1212. [PubMed] [Google Scholar]
- Ichinose M., Barnes P. J. Histamine H3-receptors modulate nonadrenergic noncholinergic neural bronchoconstriction in guinea-pig in vivo. Eur J Pharmacol. 1989 Dec 12;174(1):49–55. doi: 10.1016/0014-2999(89)90872-8. [DOI] [PubMed] [Google Scholar]
- Karlsson J. A. A role for capsaicin sensitive, tachykinin containing nerves in chronic coughing and sneezing but not in asthma: a hypothesis. Thorax. 1993 Apr;48(4):396–400. doi: 10.1136/thx.48.4.396. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Karlsson J. A., Lanner A. S., Persson C. G. Airway opioid receptors mediate inhibition of cough and reflex bronchoconstriction in guinea pigs. J Pharmacol Exp Ther. 1990 Feb;252(2):863–868. [PubMed] [Google Scholar]
- Karlsson J. A., Sant'Ambrogio G., Widdicombe J. Afferent neural pathways in cough and reflex bronchoconstriction. J Appl Physiol (1985) 1988 Sep;65(3):1007–1023. doi: 10.1152/jappl.1988.65.3.1007. [DOI] [PubMed] [Google Scholar]
- Kotlikoff M. I. Potassium channels in airway smooth muscle: a tale of two channels. Pharmacol Ther. 1993;58(1):1–12. doi: 10.1016/0163-7258(93)90064-k. [DOI] [PubMed] [Google Scholar]
- Lalloo U. G., Fox A. J., Belvisi M. G., Chung K. F., Barnes P. J. Capsazepine inhibits cough induced by capsaicin and citric acid but not by hypertonic saline in guinea pigs. J Appl Physiol (1985) 1995 Oct;79(4):1082–1087. doi: 10.1152/jappl.1995.79.4.1082. [DOI] [PubMed] [Google Scholar]
- Laurent F., Michel A., Bonnet P. A., Chapat J. P., Boucard M. Evaluation of the relaxant effects of SCA40, a novel charybdotoxin-sensitive potassium channel opener, in guinea-pig isolated trachealis. Br J Pharmacol. 1993 Mar;108(3):622–626. doi: 10.1111/j.1476-5381.1993.tb12851.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Macmillan S., Sheridan R. D., Chilvers E. R., Patmore L. A comparison of the effects of SCA40, NS 004 and NS 1619 on large conductance Ca(2+)-activated K+ channels in bovine tracheal smooth muscle cells in culture. Br J Pharmacol. 1995 Sep;116(1):1656–1660. doi: 10.1111/j.1476-5381.1995.tb16387.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Maggi C. A., Patacchini R., Rovero P., Santicioli P. Tachykinin receptors and noncholinergic bronchoconstriction in the guinea-pig isolated bronchi. Am Rev Respir Dis. 1991 Aug;144(2):363–367. doi: 10.1164/ajrccm/144.2.363. [DOI] [PubMed] [Google Scholar]
- Murray M. A., Berry J. L., Cook S. J., Foster R. W., Green K. A., Small R. C. Guinea-pig isolated trachealis: the effects of charybdotoxin on mechanical activity, membrane potential changes and the activity of plasmalemmal K(+)-channels. Br J Pharmacol. 1991 Jul;103(3):1814–1818. doi: 10.1111/j.1476-5381.1991.tb09868.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Nichol G., Nix A., Barnes P. J., Chung K. F. Prostaglandin F2 alpha enhancement of capsaicin induced cough in man: modulation by beta 2 adrenergic and anticholinergic drugs. Thorax. 1990 Sep;45(9):694–698. doi: 10.1136/thx.45.9.694. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Olesen S. P., Munch E., Moldt P., Drejer J. Selective activation of Ca(2+)-dependent K+ channels by novel benzimidazolone. Eur J Pharmacol. 1994 Jan 4;251(1):53–59. doi: 10.1016/0014-2999(94)90442-1. [DOI] [PubMed] [Google Scholar]
- Olesen S. P., Munch E., Wätjen F., Drejer J. NS 004--an activator of Ca(2+)-dependent K+ channels in cerebellar granule cells. Neuroreport. 1994 Apr 14;5(8):1001–1004. doi: 10.1097/00001756-199404000-00037. [DOI] [PubMed] [Google Scholar]
- Pisarri T. E., Jonzon A., Coleridge H. M., Coleridge J. C. Vagal afferent and reflex responses to changes in surface osmolarity in lower airways of dogs. J Appl Physiol (1985) 1992 Dec;73(6):2305–2313. doi: 10.1152/jappl.1992.73.6.2305. [DOI] [PubMed] [Google Scholar]
- Sant'Ambrogio G. Nervous receptors of the tracheobronchial tree. Annu Rev Physiol. 1987;49:611–627. doi: 10.1146/annurev.ph.49.030187.003143. [DOI] [PubMed] [Google Scholar]
- Sellers A. J., Ashford M. L. Activation of BKCa channels in acutely dissociated neurones from the rat ventromedial hypothalamus by NS 1619. Br J Pharmacol. 1994 Nov;113(3):659–661. doi: 10.1111/j.1476-5381.1994.tb17041.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Snetkov V. A., Hirst S. J., Twort C. H., Ward J. P. Potassium currents in human freshly isolated bronchial smooth muscle cells. Br J Pharmacol. 1995 Jul;115(6):1117–1125. doi: 10.1111/j.1476-5381.1995.tb15926.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Stretton D., Miura M., Belvisi M. G., Barnes P. J. Calcium-activated potassium channels mediate prejunctional inhibition of peripheral sensory nerves. Proc Natl Acad Sci U S A. 1992 Feb 15;89(4):1325–1329. doi: 10.1073/pnas.89.4.1325. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Torphy T. J. Beta-adrenoceptors, cAMP and airway smooth muscle relaxation: challenges to the dogma. Trends Pharmacol Sci. 1994 Oct;15(10):370–374. doi: 10.1016/0165-6147(94)90157-0. [DOI] [PubMed] [Google Scholar]
- WIDDICOMBE J. G. Receptors in the trachea and bronchi of the cat. J Physiol. 1954 Jan;123(1):71–104. doi: 10.1113/jphysiol.1954.sp005034. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Ward J. K., Fox A. J., Barnes P. J., Belvisi M. G. Inhibition of excitatory non-adrenergic non-cholinergic bronchoconstriction in guinea-pig airways in vitro by activation of an atypical 5-HT receptor. Br J Pharmacol. 1994 Apr;111(4):1095–1102. doi: 10.1111/j.1476-5381.1994.tb14857.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Yu J., Schultz H. D., Goodman J., Coleridge J. C., Coleridge H. M., Davis B. Pulmonary rapidly adapting receptors reflexly increase airway secretion in dogs. J Appl Physiol (1985) 1989 Aug;67(2):682–687. doi: 10.1152/jappl.1989.67.2.682. [DOI] [PubMed] [Google Scholar]