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Ohlrogge AH, Frost L, Schnabel RB. Harmful Impact of Tobacco Smoking and Alcohol Consumption on the Atrial Myocardium. Cells 2022; 11:cells11162576. [PMID: 36010652 PMCID: PMC9406618 DOI: 10.3390/cells11162576] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Revised: 08/05/2022] [Accepted: 08/11/2022] [Indexed: 11/23/2022] Open
Abstract
Tobacco smoking and alcohol consumption are widespread exposures that are legal and socially accepted in many societies. Both have been widely recognized as important risk factors for diseases in all vital organ systems including cardiovascular diseases, and with clinical manifestations that are associated with atrial dysfunction, so-called atrial cardiomyopathy, especially atrial fibrillation and stroke. The pathogenesis of atrial cardiomyopathy, atrial fibrillation, and stroke in context with smoking and alcohol consumption is complex and multifactorial, involving pathophysiological mechanisms, environmental, and societal aspects. This narrative review summarizes the current literature regarding alterations in the atrial myocardium that is associated with smoking and alcohol.
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Affiliation(s)
- Amelie H. Ohlrogge
- Department of Cardiology, University Heart and Vascular Centre Hamburg, 20246 Hamburg, Germany
- German Centre for Cardiovascular Research (DZHK), Partner Site Hamburg/Kiel/Lübeck, 20246 Hamburg, Germany
| | - Lars Frost
- Diagnostic Centre, University Clinic for Development of Innovative Patient Pathways, Silkeborg Regional Hospital, 8600 Silkeborg, Denmark
- Department of Clinical Medicine, Aarhus University, 8200 Aarhus, Denmark
| | - Renate B. Schnabel
- Department of Cardiology, University Heart and Vascular Centre Hamburg, 20246 Hamburg, Germany
- German Centre for Cardiovascular Research (DZHK), Partner Site Hamburg/Kiel/Lübeck, 20246 Hamburg, Germany
- Correspondence:
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Kodirov SA. Probability that there is a mammalian counterpart of cardiac clock in insects. ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY 2022; 110:e21867. [PMID: 35106839 PMCID: PMC9250754 DOI: 10.1002/arch.21867] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Accepted: 12/25/2021] [Indexed: 05/05/2023]
Abstract
Whether or not the hyperpolarization-activated cyclic nucleotide-gated nonselective cation channel (HCN or funny current If ) is involved in pacemaking - recurrent heartbeat, it is attributed to electrical activities in all excitable cells, including those of invertebrates. In latter group of animals prevailingly the electrical signals and function of heart in terms of chrono- and inotropy are elucidated. Although in simpler models including insects experimental outcomes are reproducible and robust, involvement of "cardiac clock" mechanism in pacemaking is not conclusive. In this assay, the mechanisms of heartbeat are synthesized by focused comparisons between insect and mammalian hearts.
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Affiliation(s)
- Sodikdjon A. Kodirov
- Pavlov Institute of Physiology, Russian Academy of Sciences, Saint Petersburg, Russia
- Department of Biological Sciences, University of Texas at Brownsville, Brownsville, Texas, USA
- Instituto de Medicina Molecular, Universidade de Lisboa, Lisbon, Portugal
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Bébarová M, Horáková Z, Kula R. Addictive drugs, arrhythmias, and cardiac inward rectifiers. Europace 2017; 19:346-355. [PMID: 27302393 DOI: 10.1093/europace/euw071] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Accepted: 02/20/2016] [Indexed: 12/30/2022] Open
Abstract
In many addictive drugs including alcohol and nicotine, proarrhythmic effects were reported. This review provides an overview of the current knowledge in this field (with a focus on the inward rectifier potassium currents) to promote the lacking data and appeal for their completion, thus, to improve understanding of the proarrhythmic potential of addictive drugs.
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Nicotine at clinically relevant concentrations affects atrial inward rectifier potassium current sensitive to acetylcholine. Naunyn Schmiedebergs Arch Pharmacol 2017; 390:471-481. [DOI: 10.1007/s00210-017-1341-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2016] [Accepted: 01/10/2017] [Indexed: 10/20/2022]
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Nicotine blocks the hyperpolarization-activated current Ih and severely impairs the oscillatory behavior of oriens-lacunosum moleculare interneurons. J Neurosci 2010; 30:10773-83. [PMID: 20702707 DOI: 10.1523/jneurosci.2446-10.2010] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
In the brain, high cognitive functions are encoded by coherent network oscillations. Key players are inhibitory interneurons that, by releasing GABA into principal cells, pace targeted cells. Among these, oriens-lacunosum moleculare (O-LM) interneurons that provide a theta frequency patterned output to distal dendrites of pyramidal cells are endowed with HCN channels responsible for the slowly activating inwardly rectifying Ih current and their pacemaking activity. Here we show that, in transgenic mice expressing EGFP (enhanced green fluorescent protein) in a subset of stratum oriens somatostatin-containing interneurons that mostly comprise O-LM cells, nicotine, the active component of tobacco, reduced Ih and the oscillatory behavior of O-LM interneurons. In cells hyperpolarized at -90 mV, nicotine suppressed the theta resonance in the same way as ZD 7288 (4-ethylphenylamino-1,2-dimethyl-6-methylaminopyrimidinium chloride), a selective blocker of Ih. Nicotine blocked Ih in a concentration-dependent way with an EC50 of 62 nm. Similar effects were produced by epibatidine, a structural analog of nicotine. The effects of nicotine and epibatidine were independent on nicotinic ACh receptor (nAChR) activation because they persisted in the presence of nAChR antagonists. Furthermore, nicotine slowed down the interspike depolarizing slope and the firing rate, thus severely disrupting the oscillatory behavior of O-LM cells. Molecular modeling suggests that, similarly to ZD 7288, nicotine and epibatidine directly bind to the inner pore of the HCN channels. It is therefore likely that nicotine severely influences rhythmogenesis and high cognitive functions in smokers.
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Kimura J, Ono T, Sakamoto K, Ito E, Watanabe S, Maeda S, Shikama Y, Yatabe MS, Matsuoka I. Na+ -Ca2+ exchanger expression and its modulation. Biol Pharm Bull 2009; 32:325-31. [PMID: 19252272 DOI: 10.1248/bpb.32.325] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Here we reviewed our recent work on the chronic effects of nicotine on the Na+ -Ca2+ exchanger (NCX) gene and protein expressions in various organs of rats treated with nicotine in the drinking water for 4-12 weeks. Microarray analysis and reverse transcriptase-polymerase chain reaction (RT-PCR) did not detect significant changes in NCX mRNA expression in cerebral cortex, hippocampus, heart and skeletal muscle. However, NCX1 protein was up-regulated by nicotine in cerebral cortex and hippocampus, but was down-regulated in the heart. NCX2 protein was up-regulated by nicotine in hippocampus. We suggest that although mRNA change was insignificant, NCX protein expression was altered by chronic nicotine administration in brain and heart in rats. We also reviewed our work on modulators of NCX gene expression and function in cardiac myocytes.
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Affiliation(s)
- Junko Kimura
- Department of Pharmacology, Fukushima Medical University, School of Medicine, Japan.
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Abstract
Smoking is a leading cause of cardiovascular disease, hypertension, myocardial infarction, and stroke. Nicotine is one of the components of cigarette smoke. Nicotine effects on the cardiovascular system reflect the activity of the nicotine receptors centrally and on peripheral autonomic ganglia. It has been found that cigarette smoke extract-induced contraction of porcine coronary arteries is related to superoxide anion-mediated degradation of nitric oxide. Treatment of rabbit aortas with an oxygen free radicals scavenger attenuated cigarette smoke impairment of arterial relaxation. Treatment of smokers with vitamin C, an antioxidant, improved impaired endothelium-dependent reactivity of large peripheral arteries. Thus it appears that chronic smoking and acute exposure to cigarette smoke extract may alter endothelium-dependent reactivity via the production of oxygen derived free radicals. This review discusses the effects of nicotine on resistance arterioles, compliance arteries, smooth muscle cells, and ion channels in the cardiovascular system. We discuss studies performed on humans, nicotine-exposed animals, and cell cultures yielding varying and inconsistent results that may be due to differences in experimental design, species, and the dose of exposure. Nicotine exposure appears to induce a combination of free radical production, vascular wall adhesion, and a reduction of fibrinolytic activity in the plasma.
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Affiliation(s)
- Salma Toma Hanna
- Department of Physiology, University of Saskatchewan, Saskatoon, Canada.
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Hanna ST, Cao K, Sun X, Wang R. Mediation of the Effect of Nicotine on Kir6.1 Channels by Superoxide Anion Production. J Cardiovasc Pharmacol 2005; 45:447-55. [PMID: 15821440 DOI: 10.1097/01.fjc.0000159046.35241.4e] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
KATP channels are a complex of regulatory sulfonylurea receptor subunits and the pore-forming inward rectifiers such as Kir6.1. Using the whole-cell patch-clamp technique, we investigated the interaction of nicotine with the Kir6.1 subunit as well as the underlying mechanism. Stable expression of Kir6.1 in HEK-293 cells yielded a detectable inward rectifier KATP current. This inward current was significantly inhibited by PNU-37883A and by a specific anti-Kir6.1 antibody. Nicotine at 30 and 100 microM increased Kir6.1 currents by 42 +/- 11.8% and 26.2 +/- 14.6%, respectively (n = 4-6, P < 0.05). In contrast, nicotine at 1-3 mM inhibited Kir6.1 currents (P < 0.05). Nicotine at 100 microM increased the production of superoxide anion (O2) by 20.3 +/- 5.7%, whereas at 1 mM it significantly decreased the production of O2 by 37.7 +/- 4.3%. Coapplication of hypoxanthine (HX) and xanthine oxidase (XO) to the transfected HEK-293 cells resulted in a significant and reproducible increase in Kir6.1 currents (P < 0.05). The stimulatory effect of HX/XO on Kir6.1 current was abolished by tempol, a scavenger of O2. Tempol also abolished the stimulatory effect of 30 muM nicotine on Kir6.1 currents. In conclusion, nicotine stimulates Kir6.1 channel at least in part through the production of O2.
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Affiliation(s)
- Salma Toma Hanna
- Department of Physiology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
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Suzuki J, Bayna E, Dalle Molle E, Lew WYW. Nicotine inhibits cardiac apoptosis induced by lipopolysaccharide in rats. J Am Coll Cardiol 2003; 41:482-8. [PMID: 12575980 DOI: 10.1016/s0735-1097(02)02820-6] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
OBJECTIVES Apoptosis develops in several heart diseases, but the therapeutic options are limited. It was hypothesized that nicotine, which inhibits apoptosis in several cells, inhibits cardiac apoptosis induced by lipopolysaccharide (LPS). BACKGROUND Over-the-counter nicotine produces sustained levels (10 to 25 ng/ml) that may be antiapoptotic. Low levels of LPS induce apoptosis by activating tissue renin-angiotensin to stimulate angiotensin II, type 1 (AT(1)) receptors in cardiac myocytes. METHODS Adult Sprague Dawley rats were pretreated with nicotine (6 mg/kg/day) or saline for seven to ten days (miniosmotic pumps). The LPS (1 mg/kg) was injected intravenously. Toll-like receptor 4 (TLR4) and angiotensinogen messenger ribonucleic acid (mRNA) were measured in the heart after 0, 4, 8, 16, and 24 h. Cardiac apoptosis was measured by terminal deoxy-nucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) staining after 24 h. In vitro effects of LPS (10 ng/ml, 24 h) were studied in cardiac myocytes isolated from rats pretreated with nicotine for 7 to 10 days, or after pre-exposing myocytes to nicotine (15 ng/ml) for 1, 4, 16, or 24 h. RESULTS Neither nicotine nor LPS affected systolic blood pressure. The LPS increased cardiac apoptosis after 24 h in saline-treated, but not nicotine-treated rats, despite similar increases in cardiac TLR4 and angiotensinogen mRNA over 8 to 16 h. The LPS-induced apoptosis was blocked by pre-exposing myocytes to nicotine for 4 to 24 h (partial inhibition after 1 h). Nicotine did not inhibit apoptosis induced by angiotensin II (100 nM, 24 h). CONCLUSIONS Therapeutic levels of nicotine inhibit LPS-induced cardiac apoptosis. This occurs after LPS increases TLR4 and angiotensinogen mRNA, but proximal to AT(1) receptor activation. Nicotine may be a novel inhibitor of cardiac apoptosis in conditions associated with circulating LPS (e.g., decompensated heart failure, acute and chronic infections).
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Affiliation(s)
- Jun Suzuki
- Cardiology Section, Department of Medicine, V.A. San Diego Healthcare System and University of California, 3350 La Jolla Village Drive, San Diego, CA 92161, USA
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Satoh H. Modulation by nicotine of the ionic currents in guinea pig ventricular cardiomyocytes. Relatively higher sensitivity to IKr and IKl. Vascul Pharmacol 2002; 39:55-61. [PMID: 12616991 DOI: 10.1016/s1537-1891(02)00194-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The effects of nicotine on the ionic currents in guinea pig cardiomyocytes were investigated using a whole-cell voltage-clamp technique. Nicotine (30 microM to 1 mM) inhibited the ionic currents in a concentration-dependent manner. Nicotine at 30 microM did not affect the Ca2+ current (ICa), but at 300 microM inhibited ICa at 10 mV by 29.3 +/- 2.4% (n = 6, P < .01) and at 1 mM almost blocked the ICa (by approximately 90%, n = 5, P < .001). After 5- to 10-min washout, these responses had 50-70% recovery. The fast time constant (tau f) of the inactivation phase for ICa at 10 mV was not affected, but the slow one (tau s) increased from 35.7 +/- 2.8 to 39.5 +/- 2.4 ms (n = 7) at 300 microM nicotine. Nicotine at 100 microM also inhibited the delayed rectifier K+ current (IK) at 60 mV by 42.7 +/- 3.0% (n = 7, P < .01), and at 30 microM inhibited the inwardly rectifying K+ current (IKl) at -110 mV by 43.0 +/- 2.5% (n = 7, P < .01). The responses to nicotine were not significantly modified by atropine, hexamethonium, and nicotine receptor antagonists (d-tubocurarine and benzoquinonium). The IK is composed of two components for rapidly and slowly activated currents (IKr and IKs). Nicotine markedly decreased the tail current of IKr, but had less or no effect on that of IKs. However, the activation and inactivation kinetics (d infinity and f infinity) for ICa and its activation kinetics (P infinity) for IKr and IKs were not modified. These results suggest that nicotine inhibits the ionic currents with relatively higher sensitivity to IKl and IKr, resulting in modulation of the cardiac functions.
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Affiliation(s)
- Hiroyasu Satoh
- Department of Pharmacology, Division of Molecular and Cellular Biology, Nara Medical University, Kashihara, Nara 634-8521, Japan.
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Wang H, Shi H, Zhang L, Pourrier M, Yang B, Nattel S, Wang Z. Nicotine is a potent blocker of the cardiac A-type K(+) channels. Effects on cloned Kv4.3 channels and native transient outward current. Circulation 2000; 102:1165-71. [PMID: 10973847 DOI: 10.1161/01.cir.102.10.1165] [Citation(s) in RCA: 88] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Nicotine is a main constituent of cigarette smoke and smokeless tobacco, known to increase the risk of sudden cardiac death. This study aimed at establishing ionic mechanisms underlying potential electrophysiological effects of nicotine. METHODS AND RESULTS Effects of nicotine on Kv4.3 and Kv4.2 channels expressed in Xenopus oocytes were studied at the whole-cell and single-channel levels. The effects of nicotine on the transient outward K(+) current (I:(to)) were studied by use of whole-cell patch-clamp techniques in canine ventricular myocytes. Nicotine potently inhibited Kv4 current. The concentration for half-maximal inhibition (IC(50)) was 40+/-4 nmol/L, and the current was abolished by 100 micromol/L nicotine. The IC(50) for block of native I:(to) was 270+/-43 nmol/L. The steady-state activation properties of Kv4.3 and I:(to) were unaltered by nicotine, whereas positive shifts of the inactivation curves were observed. Of the total inhibition of Kv4.3 and I:(to) by nicotine, 40% was due to tonic block and 60% was attributable to use-dependent block. Activation, inactivation, and reactivation kinetics were not significantly changed by nicotine. Nicotine reduced single-channel conductance, open probability, and open time but increased the closed time of Kv4.3. The effects of nicotine were not altered by antagonists to various neurotransmitter receptors, indicating direct effects on I:(to) channels. CONCLUSIONS Nicotine is a potent inhibitor of cardiac A-type K(+) channels, with blockade probably due to block of closed and open channels. This action may contribute to the ability of nicotine to affect cardiac electrophysiology and induce arrhythmias.
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Affiliation(s)
- H Wang
- Department of Medicine and Research Center, Montreal Heart Institute, University of Montreal, Quebec, Canada.
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Wang H, Yang B, Zhang L, Xu D, Wang Z. Direct block of inward rectifier potassium channels by nicotine. Toxicol Appl Pharmacol 2000; 164:97-101. [PMID: 10739749 DOI: 10.1006/taap.2000.8896] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Nicotine has been shown to depolarize membrane potential and to lengthen action potential duration in isolated cardiac preparations. To investigate whether this is a consequence of direct interaction of nicotine with inward rectifier K(+) channels which are a key determinant of membrane potentials, we assessed the effects of nicotine on two cloned human inward rectifier K(+) channels, Kir2.1 and Kir2.2, expressed in Xenopus oocytes and the native inward rectifier K(+) current I(K1) in canine ventricular myocytes. Nicotine suppressed Kir2.1-expressed currents at varying potentials negative to -20 mV, with more pronounced effects on the outward current between -70 and -20 mV relative to the inward current at hyperpolarized potentials (below -70 mV). The inhibition was concentration dependent. For the outward currents recorded at -50 mV, the IC50 was 165 +/- 18 microM. Similar effects of nicotine were observed for Kir2.2. A more potent effect was seen with I(K1) in canine myocytes. Significant blockade ( approximately 60%) was found at a concentration as low as 0.5 microM and the IC50 was 4.0 +/- 0.4 microM. The effects in both oocytes and myocytes were partially reversible upon washout of nicotine. Antagonists of nicotinic receptors (mecamylamine, 100 microM), muscarinic receptors (atropine, 1 microM), and beta-adrenergic receptors (propranolol, 1 microM) all failed to restore the depressed currents, suggesting that nicotine acted directly on Kir channels, independent of catecholamine release. This property of nicotine may explain its membrane-depolarizing and action potential duration-prolonging effects in cardiac cells and may contribute in part to its ability to promote propensity for cardiac arrhythmias.
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Affiliation(s)
- H Wang
- Research Center, Montreal Heart Institute, Montreal, Quebec, H1T 1C8, Canada
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Tang G, Hanna ST, Wang R. Effects of nicotine on K+ channel currents in vascular smooth muscle cells from rat tail arteries. Eur J Pharmacol 1999; 364:247-54. [PMID: 9932730 DOI: 10.1016/s0014-2999(98)00833-4] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Intake of nicotine has been related in many cases to acute or chronic hypertension. Using the patch-clamp technique the effect of nicotine on voltage-dependent K+ channel currents in rat tail artery smooth muscle cells was studied. Nicotine at concentrations of 1-100 microM or 0.3-3 mM increased or decreased, respectively, the amplitude of the tetraethylammonium-sensitive K+ currents. Pretreatment of cells with 10 microM dihydro-beta-erythroidine hydrobromide, a nicotinic receptor antagonist, abolished the excitatory effect (n=6), but not the inhibitory effect (n=10), of nicotine on K+ channel currents. The activation of nicotinic receptors with 100 microM 1,1-dimethyl-4-phenylpiperazinium iodide increased K+ channel currents by 27.4+/-3.8% (n=13, P < 0.01). Our results indicate that the excitatory and inhibitory effects of nicotine on K+ channels are respectively mediated by a nicotinic receptor-dependent mechanism and by a direct interaction of nicotine with K+ channels.
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Affiliation(s)
- G Tang
- Department of Physiology, University of Saskatchewan, Saskatoon, Canada
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Satoh H. Suppressive responses to calcium and catecholamines in immobilization stress-loaded rats. GENERAL PHARMACOLOGY 1998; 30:373-8. [PMID: 9510089 DOI: 10.1016/s0306-3623(97)00272-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
1. Modulations of electrophysiological actions on the right atria of immobilization (restraint) stress-loaded rats by extracellular Ca2+ concentration, [Ca]0, catecholamines and some drugs were examined. 2. The serum concentration of corticosterone increased compared with native rats, and peptic ulcerization was observed. 3. The stress-loaded rats had a stronger contraction and a higher sinus rate. Increasing [Ca]0 (0.9-3.6 mM) enhanced the contractile force in native rats, whereas increasing [Ca]0 inhibited it in stress-loaded rats. The cycle length decreased with an increase in [Ca]0 in native rats more than in stress-loaded rats. 4. Enhancement induced by isoprenaline (0.1-10 microM) at normal [Ca]0 was more suppressive in stress-loaded hearts. At 0.1 to 10 microM, norepinephrine and phenylephrine significantly caused a negative inotropic effect in both native and stress-loaded hearts, and norepinephrine caused a positive chronotropic effect in native hearts but not in stress hearts. 5. Both taurine and nicotine had negative inotropic and chronotropic effects in native rats. However, the drugs enhanced the contractile force in stress rats. 6. These results indicate that immobilization stress decreases the sensitivities to [Ca]0, and increasing [Ca]0 easily elicits Ca2+ overload. Low sensitivities to sympathetic drugs also are produced by the stress loading, whereas taurine and nicotine may exhibit protective actions.
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Affiliation(s)
- H Satoh
- Department of Pharmacology, Nara Medical University, Kashihara, Japan
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