On the molecular nature of the lidocaine receptor of cardiac Na+ channels. Modification of block by alterations in the alpha-subunit III-IV interdomain.

The mechanism of inhibition of Na+ channels by lidocaine has been suggested to involve low-affinity binding to rested states and high-affinity binding to the inactivated state of the channel, implying either multiple receptor sites or allosteric modulation of receptor affinity. Alternatively, the lidocaine receptor may be guarded by the channel gates. To test these distinct hypotheses, inhibition of Na+ channels by lidocaine was studied by voltage-clamp methods in both native and heterologous expression systems. Native Na+ channels were studied in guinea pig ventricular myocytes, and recombinant human heart Na+ channels were expressed in Xenopus laevis oocytes. Fast inactivation was eliminated by mutating three amino acids (isoleucine, phenylalanine, and methionine) in the III-IV interdomain to glutamines or by enzymatic digestion with alpha-chymotrypsin. In channels with intact fast inactivation, lidocaine block developed with a time constant of 589 +/- 42 ms (n = 7) at membrane potentials between -50 and +20 mV, as measured by use of twin pulse protocols. The IC50 was 36 +/- 1.8 mumol/L. Control channels inactivated within 20 ms, and slow inactivation developed much later (time constant of slow inactivation, 6.2 +/- 0.36 s). The major component of block developed long after activated and open channels were no longer available for drug binding. Control channels recovered fully from inactivation in < 50 ms at -120 mV (time constant, 11 +/- 0.5 ms; n = 50).(ABSTRACT TRUNCATED AT 250 WORDS)

[1]  G. Strichartz,et al.  Inhibition of sodium currents by local anesthetics in chloramine-T- treated squid axons. The role of channel activation , 1987, The Journal of general physiology.

[2]  J. Changeux,et al.  Allosteric proteins and cellular control systems. , 1963, Journal of molecular biology.

[3]  F. Conti,et al.  Structural parts involved in activation and inactivation of the sodium channel , 1989, Nature.

[4]  R. Horn,et al.  Chimeric study of sodium channels from rat skeletal and cardiac muscle , 1992, FEBS letters.

[5]  W. Catterall,et al.  Inhibition of binding of [3H]batrachotoxinin A 20-alpha-benzoate to sodium channels by local anesthetics. , 1984, Molecular pharmacology.

[6]  C. Starmer,et al.  Modeling ion channel blockade at guarded binding sites: application to tertiary drugs. , 1986, The American journal of physiology.

[7]  F. Bezanilla,et al.  Destruction of Sodium Conductance Inactivation in Squid Axons Perfused with Pronase , 1973, The Journal of general physiology.

[8]  R Horn,et al.  Effect of N-bromoacetamide on single sodium channel currents in excised membrane patches , 1982, The Journal of general physiology.

[9]  C. Starmer,et al.  Blockade of Cardiac Sodium Channels by Lidocaine Single-Channel Analysis , 1989, Circulation research.

[10]  M. Janse.  Molecular and cellular mechanisms of antiarrhythmic agents: Editor: Luc Hondeghem Futura Publishing Company, Mount Kisco, New York, 1989; 338 pp., $57.00; ISBN 0-87993-379-8 , 1991 .

[11]  E. Moczydlowski,et al.  BLOCKING PHARMACOLOGY OF BATRACHOTOXIN-ACTIVATED SODIUM CHANNELS , 1986 .

[12]  L. Hondeghem,et al.  Evidence for Two Components of Sodium Channel Block by Lidocaine in Isolated Cardiac Myocytes , 1988, Circulation research.

[13]  B. Hille,et al.  Local anesthetics: hydrophilic and hydrophobic pathways for the drug- receptor reaction , 1977, The Journal of general physiology.

[14]  B. Katzung,et al.  Time- and voltage-dependent interactions of antiarrhythmic drugs with cardiac sodium channels. , 1977, Biochimica et biophysica acta.

[15]  B. Sakmann,et al.  Single-Channel Recording , 1995, Springer US.

[16]  A. Brown,et al.  Sodium current depression by lidocaine and quinidine in isolated ventricular cells , 1981, Nature.

[17]  Fred J. Sigworth,et al.  Fitting and Statistical Analysis of Single-Channel Records , 1983 .

[18]  R Horn,et al.  Primary structure and functional expression of the human cardiac tetrodotoxin-insensitive voltage-dependent sodium channel. , 1992, Proceedings of the National Academy of Sciences of the United States of America.

[19]  C. January,et al.  Circulation Research an Official Journal of the American Heart Association New Studies of the Excitatory Sodium Currents in Heart Muscle , 2022 .

[20]  B. Katzung,et al.  Antiarrhythmic agents: the modulated receptor mechanism of action of sodium and calcium channel-blocking drugs. , 1984, Annual review of pharmacology and toxicology.

[21]  W. Catterall,et al.  Structure and function of voltage-sensitive ion channels. , 1988, Science.

[22]  B. Khodorov.  Role of Inactivation in Local Anesthetic Action , 1991, Annals of the New York Academy of Sciences.

[23]  C. Starmer,et al.  Phasic ion channel blockade. A kinetic model and parameter estimation procedure. , 1985, Molecular pharmacology.

[24]  R Horn,et al.  Statistical properties of single sodium channels , 1984, The Journal of general physiology.

[25]  T. McDonald,et al.  Use-dependent block of single sodium channels by lidocaine in guinea pig ventricular myocytes. , 1989, Biophysical journal.

[26]  C. Starmer,et al.  Ligand binding to transiently accessible sites: mechanisms for varying apparent binding rates. , 1987, Journal of theoretical biology.

[27]  A. Grant.  Evolving Concepts of Cardiac Sodium Channel Function , 1990 .

[28]  A L Goldin,et al.  A cluster of hydrophobic amino acid residues required for fast Na(+)-channel inactivation. , 1992, Proceedings of the National Academy of Sciences of the United States of America.

[29]  S. Roberds,et al.  Heteromultimeric assembly of human potassium channels. Molecular basis of a transient outward current? , 1993, Circulation research.

[30]  G. Strichartz,et al.  The Inhibition of Sodium Currents in Myelinated Nerve by Quaternary Derivatives of Lidocaine , 1973, The Journal of general physiology.

[31]  C F Starmer,et al.  Mechanisms of use-dependent block of sodium channels in excitable membranes by local anesthetics. , 1984, Biophysical journal.

[32]  B. Hille.  Ionic channels of excitable membranes , 2001 .

[33]  C. Armstrong.  Interaction of Tetraethylammonium Ion Derivatives with the Potassium Channels of Giant Axons , 1971, The Journal of general physiology.

[34]  W. Catterall,et al.  Molecular determinants of state-dependent block of Na+ channels by local anesthetics. , 1994, Science.

[35]  A. L. Goldin,et al.  Amino acid residues required for fast Na(+)-channel inactivation: charge neutralizations and deletions in the III-IV linker. , 1992, Proceedings of the National Academy of Sciences of the United States of America.

[36]  Alan G. Hawkes,et al.  The Principles of the Stochastic Interpretation of Ion-Channel Mechanisms , 1983 .

[37]  L. Hondeghem,et al.  Antiarrhythmic agents: modulated receptor applications. , 1987, Circulation.

[38]  P. Bennett,et al.  Gating of cardiac Na+ channels in excised membrane patches after modification by alpha-chymotrypsin. , 1994, Biophysical journal.

[39]  K. Gingrich,et al.  Ultra‐deep blockade of Na+ channels by a quaternary ammonium ion: catalysis by a transition‐intermediate state? , 1993, The Journal of physiology.

[40]  Christopher Miller,et al.  Ion Channel Reconstitution , 1986, Springer US.