Abstract
The effects of local anaesthetic anti-arrhythmic agents (lidocaine) and Ca antagonists (Verapamil) have been examined on the early afterdepolarizations (EADs) in isolated rabbit sinoatrial (SA) node. In a nominally calcium free and magnesium free solution, strontium (0.5−4.5 mM) produced an EAD in small pieces isolated from the SA node. The additional presence of 0.02−0.6 mM lidocaine did not abolish the strontium (0.5 mM)-induced EAD. 0.6 mM lidocaine produced an increase in EAD amplitude and then abolished a prolonged action potential (AP) associated with repetitive EADs. On the other hand, the addition of 4 μM verapamil abolished the strontium (0.5 mM)-induced EAD but did not abolish the AP.
It is concluded that under conditions when the AP is not abolished, EAD blockade by lidocaine is less effective than that by verapamil.
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References
Cranefield PF: The conduction of the cardiac impulse. New York, Futura, 1975
Hoffman BF, Rosen MR: Cellular mechanisms for cardiac arrhythmias. Circ Res 49:1–15, 1981
Marban E, Robinson SW, Wier WG: Mechanisms of arrhythmogenic delayed and early afterdepolarizations in ferret ventricular muscle. J Clin Invest 78:1185–1192, 1986
January CT, Riddle JM: Early afterdepolarizations: mechanism of induction and block; a role for L-type Ca2+ current. Circ Res 64:977–990, 1989
Gonzalez MD, Vassalle M: Electrical and mechanical effects of strontium in sheep cardiac Purkinje fibers. Cardiovasc Res 23:867–881, 1989
Kohlhardt M, Herdey A, Kiibler M: Interchangeability of Ca ions and Sr ions as charge carriers of the slow inward current in mammalian myocardial fibers. Pflügers Arch 344:149–158, 1973
Gavrilescu S, Luca C: Right ventricular monophasic action potentials in patients with long QT syndrome. Br Heart J 40:1014–1018,1978
Miyamae S, Goto K: The effects of extracellular calcium removal on sinoatrial node cells treated with potassium-depleted solutions. Jpn J Physiol 36:403–409, 1986
Miyamae S, Goto K: Effects of ethylene glycol-bis-(β-aminoethyl ether)-N, N′-tetraacetic acid on rabbit sinoatrial node cells treated with cardiotonic steroids. J Pharmacol Exp Ther 245:706–717, 1988
Miyamae S: Influence of magnesium and extracellular calcium reduction on ouabaintreated sinoatrial node cells in rabbit heart. Pharmacol Toxicol 65:192–197, 1989
Dörrscheidt-Käfer M: The action of Ca2+, Mg2+ and H+ on the contraction threshold of frog skeletal muscle. Pfliigers Arch 362:33–41, 1976
Miller DJ, Mörchen A: On the effects of divalent cations and ethylene glycol-bis-(β-aminoethyl ether) N,N,N′, N′-tetraacetate on action potential duration in frog heart. J Gen Physiol 71:47–67, 1978
Brachmann J, Scherlay BJ, Rosenstraukh LV, Lazzara R: Bradycardia-dependent triggered activity: relevance to drug-induced multiform ventricular tachycardia. Circulation 68:846–856, 1983
Roden DM, Hoffman BF: Action potential prolongation and induction of abnormal automaticity by low quinidine concentrations in canine Purkinje fibers. Relationship to potassium and cycle length. Circ Res 56:857–867, 1985
Hoffman BF, Dangman KH: Mechanisms for cardiac arrhythmias. Experientia 43:1049–1056, 1987
Kupersmith J, Hoff P, Duo GS: In vitro characteristics of repolarization abnormality — a possible cause of arrhythmias. J Electrocardiol 19:361–370, 1986
Rosen KM, Lau SH, Weiss MB, Damato AN: The effect of lidocaine on atrioventricular and intraventricular conduction in man. Am J cardiol 25:1–5, 1970
Hagiwara S, Byerly L: Calcium channel. Annu Rev Neurosci 4:69–125, 1981
Vereecke J, Carmeliet E: Sr action potentials in cardiac Purkinje fibers. 1. Evidence for a regenerative increase in Sr conductance. Pflügers Arch 322:60–72, 1971
Sakai T, Fujii S, Hirota A, Kamino K: Optical evidence for calcium-action potentials in early embryonic precontractile chick heart using a potential-sensitive dye. J Membrane Biol 72:205–212, 1983
Lee KS, Tsien RW: Mechanism of calcium channel blockade by verapamil, D600, diltiazem and nitrendipine in single dialysed heart cells. Nature 302:790–794, 1983
Josephson IR: Lidocaine blocks Na, Ca and K currents of chick ventricular myocytes. J Mol Cell Cardiol 20:593–604, 1988
Trautwein W: Membrane currents in cardiac muscle fibers. Physiol Rev 53:793–835, 1973
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Miyamae, Si., Matsuda, T., Goto, K. et al. Effects of lidocaine and verapamil on early afterdepolarizations in isolated rabbit sinoatrial node. J Anesth 5, 213–220 (1991). https://doi.org/10.1007/s0054010050213
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DOI: https://doi.org/10.1007/s0054010050213