title: Interaction of local anesthetics with the K (+) channel pore domain: KcsA as a model for drug-dependent tetramer stability.
abstract: Local anesthetics and related drugs block ionic currents of Na (+) , K (+) and Ca ( 2+) conducted across the cell membrane by voltage-dependent ion channels. Many of these drugs bind in the permeation pathway, occlude the pore and stop ion movement. However channel-blocking drugs have also been associated with decreased membrane stability of certain tetrameric K (+) channels, similar to the destabilization of channel function observed at low extracellular K (+) concentration. Such drug-dependent stability may result from electrostatic repulsion of K (+) from the selectivity filter by a cationic drug molecule bound in the central cavity of the channel. In this study we used the pore domain of the KcsA K (+) channel protein to test this hypothesis experimentally with a biochemical assay of tetramer stability and theoretically by computational simulation of local anesthetic docking to the central cavity. We find that two common local anesthetics, lidocaine and tetracaine, promote thermal dissociation of the KcsA tetramer in a K (+) -dependent fashion. Docking simulations of these drugs with open, open-inactivated and closed crystal structures of KcsA yield many energetically favorable drug-channel complexes characterized by nonbonded attraction to pore-lining residues and electrostatic repulsion of K (+) . The results suggest that binding of cationic drugs to the inner cavity can reduce tetramer stability of K (+) channels.
authors.affiliation: Neuroscience & Physiology, SUNY Upstate Medical University, Syracuse, NY, USA.
authors.forename: Noel W
authors.initials: NW
authors.lastname: Gray
authors.forename: Boris S
authors.initials: BS
authors.lastname: Zhorov
authors.forename: Edward G
authors.initials: EG
authors.lastname: Moczydlowski
mesh_terms: D000779:Anesthetics, Local / Q000737:chemistry* / Q000378:metabolism* / Q000494:pharmacology; D008958:Models, Molecular; D015221:Potassium Channels / Q000737:chemistry* / Q000378:metabolism*; D055503:Protein Multimerization / Q000187:drug effects*; D055550:Protein Stability / Q000187:drug effects; D017434:Protein Structure, Tertiary
chemical_list: D000779:Anesthetics, Local; D015221:Potassium Channels
keywords: K+ channels; ion channels; lidocaine; local anesthetics; membrane protein; tetracaine
references.citation: Biophys J. 1995 Aug;69(2):418-27
references.pmid: 8527655
references.citation: J Biol Chem. 2004 Jan 2;279(1):394-400
references.pmid: 14578345
references.citation: Biophys J. 1981 May;34(2):271-91
references.pmid: 7236852
references.citation: Proc Natl Acad Sci U S A. 1997 Nov 25;94(24):13335-8
references.pmid: 9371846
references.citation: Nature. 2010 Jul 8;466(7303):203-8
references.pmid: 20613835
references.citation: Pflugers Arch. 2005 Jul;450(4):255-61
references.pmid: 15909181
references.citation: Biochemistry. 1997 Aug 19;36(33):10335-42
references.pmid: 9254633
references.citation: J Physiol. 2010 Aug 1;588(Pt 15):2691-706
references.pmid: 20547671
references.citation: Nature. 2001 Nov 1;414(6859):37-42
references.pmid: 11689935
references.citation: Circ Res. 2009 Jun 19;104(12):1390-8
references.pmid: 19443837
references.citation: J Gen Physiol. 2005 Sep;126(3):271-83
references.pmid: 16129774
references.citation: Anesth Analg. 1994 Sep;79(3):490-4
references.pmid: 8067553
references.citation: Anesthesiology. 1990 Apr;72(4):711-34
references.pmid: 2157353
references.citation: Proc Natl Acad Sci U S A. 2000 Oct 24;97(22):12329-33
references.pmid: 11005845
references.citation: Science. 2005 Aug 5;309(5736):897-903
references.pmid: 16002581
references.citation: Br J Pharmacol. 2006 Nov;149(5):481-9
references.pmid: 16967046
references.citation: Biophys J. 2005 Aug;89(2):1020-9
references.pmid: 15908577
references.citation: J Gen Physiol. 1971 Oct;58(4):413-37
references.pmid: 5112659
references.citation: Novartis Found Symp. 2005;266:57-69; discussion 70-4, 95-9
references.pmid: 16050262
references.citation: Nature. 2000 Apr 20;404(6780):881-4
references.pmid: 10786795
references.citation: Trends Pharmacol Sci. 2005 Mar;26(3):119-24
references.pmid: 15749156
references.citation: J Mol Biol. 2003 Nov 7;333(5):965-75
references.pmid: 14583193
references.citation: J Mol Graph Model. 2008 Sep;27(2):178-87
references.pmid: 18485768
references.citation: Mol Pharmacol. 2009 Apr;75(4):927-37
references.pmid: 19139152
references.citation: J Clin Invest. 2009 Sep;119(9):2531-4
references.pmid: 19726880
references.citation: Reg Anesth Pain Med. 2005 May-Jun;30(3):260-74
references.pmid: 15898030
references.citation: J Gen Physiol. 2001 Dec;118(6):639-48
references.pmid: 11723158
references.citation: J Biol Chem. 2009 Jan 30;284(5):2854-2860
references.pmid: 19033439
references.citation: J Gen Physiol. 1977 Apr;69(4):497-515
references.pmid: 300786
references.citation: J Mol Biol. 2007 Sep 21;372(3):774-97
references.pmid: 17681537
references.citation: J Membr Biol. 2004 Sep 1;201(1):1-8
references.pmid: 15635807
references.citation: Nature. 2001 Jun 7;411(6838):657-61
references.pmid: 11395760
references.citation: J Pharmacol Sci. 2008 Sep;108(1):49-55
references.pmid: 18818480
references.citation: J Comput Chem. 2010 Jan 15;31(1):133-43
references.pmid: 19421996
references.citation: Nat Struct Mol Biol. 2009 Dec;16(12):1317-24
references.pmid: 19946269
references.citation: Biophys J. 2005 Feb;88(2):1018-29
references.pmid: 15556975
references.citation: Pflugers Arch. 2010 Jul;460(2):265-76
references.pmid: 20544339
references.citation: Circ Res. 2010 Apr 2;106(6):1072-82
references.pmid: 20133899
references.citation: Biochemistry. 2007 Jan 30;46(4):1079-90
references.pmid: 17240991
references.citation: Am J Physiol. 1959 May;196(5):1071-8
references.pmid: 13649934
references.citation: J Mol Biol. 2007 Jan 19;365(3):649-62
references.pmid: 17070844
references.citation: J Physiol. 2012 Jun 1;590(11):2577-89
references.pmid: 22473783
references.citation: Biophys J. 2007 Sep 1;93(5):1557-70
references.pmid: 17496040
references.citation: J Comput Chem. 1986 Apr;7(2):230-252
references.pmid: 29160584
references.citation: J Membr Biol. 1980 Dec 15;57(2):119-31
references.pmid: 6259362
references.citation: J Biol Chem. 2002 Jun 28;277(26):23587-95
references.pmid: 11960982
references.citation: Nature. 2001 Oct 25;413(6858):809-13
references.pmid: 11677598
references.citation: Expert Opin Investig Drugs. 2009 Apr;18(4):399-416
references.pmid: 19335273
references.citation: Proc Natl Acad Sci U S A. 1987 Oct;84(19):6611-5
references.pmid: 3477791
references.citation: J Physiol. 1997 Feb 15;499 ( Pt 1):3-15
references.pmid: 9061636
references.citation: Biophys J. 2001 Nov;81(5):2606-13
references.pmid: 11606274
references.citation: Nature. 2001 Nov 1;414(6859):43-8
references.pmid: 11689936
references.citation: Biochemistry. 2008 May 13;47(19):5354-67
references.pmid: 18419132
references.citation: J Mol Biol. 2007 Feb 23;366(3):806-14
references.pmid: 17196615
references.citation: J Gen Physiol. 1980 Jan;75(1):61-78
references.pmid: 7359118
references.citation: PLoS One. 2009 Oct 16;4(10):e7496
references.pmid: 19834614
references.citation: Biophys J. 2008 Feb 1;94(3):820-31
references.pmid: 17905851
references.citation: J Clin Invest. 2009 Sep;119(9):2745-57
references.pmid: 19726881
references.citation: Bioorg Med Chem Lett. 2010 Apr 15;20(8):2493-6
references.pmid: 20304642
references.citation: J Comput Aided Mol Des. 2010 Feb;24(2):91-105
references.pmid: 20119653
references.citation: Mol Pharmacol. 2006 May;69(5):1709-16
references.pmid: 16474003
references.citation: Nature. 2006 Mar 23;440(7083):463-9
references.pmid: 16554806
references.citation: J Pharmacol Toxicol Methods. 2005 Jul-Aug;52(1):136-45
references.pmid: 15950494
references.citation: J Gen Physiol. 2000 Mar;115(3):269-72
references.pmid: 10694255
references.citation: J Gen Physiol. 1999 Sep;114(3):365-76
references.pmid: 10469727
references.citation: Trends Pharmacol Sci. 2010 Aug;31(8):364-71
references.pmid: 20605645
references.citation: J Biol Chem. 2002 Feb 15;277(7):4989-98
references.pmid: 11741928
references.citation: Proc Natl Acad Sci U S A. 2011 Jul 19;108(29):11896-9
references.pmid: 21730186
references.citation: Proc Natl Acad Sci U S A. 2002 Sep 17;99(19):12461-6
references.pmid: 12209010
references.citation: Mol Pharmacol. 2008 Oct;74(4):1033-45
references.pmid: 18653802
references.citation: Nat Struct Mol Biol. 2005 May;12(5):454-9
references.pmid: 15852022