The anesthetic bupivacaine induces cardiotoxicity by targeting L-type voltage-dependent calcium channels

Objective Bupivacaine is an amide local anesthetic with possible side effects that include an irregular heart rate. However, the mechanism of bupivacaine-induced cardiotoxicity has not been fully elucidated, thus we aimed to examine this mechanism. Methods We performed electrocardiogram recordings to detect action potential waveforms in Sprague Dawley rats after application of bupivacaine, while calcium (Ca2+) currents in neonatal rat ventricular cells were examined by patch clamp recording. Western blot and quantitative real-time polymerase chain reaction assays were used to detect the expression levels of targets of interest. Results In the present study, after application of bupivacaine, abnormal action potential waveforms were detected in Sprague Dawley rats by electrocardiogram recordings, while decreased Ca2+ currents were confirmed in neonatal rat ventricular cells by patch clamp recording. These alterations may be attributed to a deficiency of CaV1.3 (L-type) Ca2+ channels, which may be regulated by the multifunctional protein calreticulin. Conclusions The present study identifies a possible role of the calreticulin–CaV1.3 axis in bupivacaine-induced abnormal action potentials and Ca2+ currents, which may lead to a better understanding anesthetic drug-induced cardiotoxicity.

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Calcium conductances and their role in the firing behavior of neonatal rat hypoglossal motoneurons

Journal of Neurophysiology ◽

10.1152/jn.1993.69.6.2137 ◽

1993 ◽

Vol 69 (6) ◽

pp. 2137-2149 ◽

Cited By ~ 90

Author(s):

F. Viana ◽

D. A. Bayliss ◽

A. J. Berger

Keyword(s):

Patch Clamp ◽

Action Potential ◽

Calcium Current ◽

Burst Firing ◽

Neonatal Rat ◽

High Threshold ◽

Calcium Spikes ◽

Firing Behavior ◽

Hypoglossal Motoneurons ◽

Voltage Dependent

1. The role of calcium conductances in action potential generation and repetitive firing behavior of hypoglossal motoneurons (HMs) was investigated using intracellular recording and patch-clamp techniques in a brain stem slice preparation of neonatal rats (0-15 days old). 2. The action potential was followed by an afterdepolarization (ADP). The ADP was voltage dependent, increasing with membrane hyperpolarization. Raising the extracellular Ca2+ concentration or replacing Ca2+ with Ba2+ increased the ADP amplitude, whereas replacement of Ca2+ with Mn2+ blocked it. The ADP was partially reduced by amiloride and low concentrations of Ni2+. 3. The firing behavior of individual neonatal HMs was influenced by membrane potential. From depolarized potentials, HMs fired tonically in response to a depolarizing current pulse, whereas from more hyperpolarized membrane potentials (more negative than -70 mV), a subset of HMs fired an initial burst of action potentials followed by a prolonged afterhyperpolarization and tonic firing. The incidence of burst-firing behavior was highest among young motoneurons and disappeared by the tenth postnatal day. In addition, prominent rebound depolarizations characterized the response of neonatal motoneurons to hyperpolarizing prepulses. 4. Pharmacological characterization of the rebound depolarization demonstrated that it was calcium dependent. Its amplitude was insensitive to tetrodotoxin and it was eliminated by replacement of Ca2+ with Mn2+ or addition of Ni2+. Amiloride (1-1.5 mM) had no effect on the rebound response or burst firing. 5. The presence of high-threshold calcium spikes was detected at all postnatal ages, but only after blockade of outward currents with intra- or extracellular tetraethylammonium. The high-threshold calcium spikes were greatly enhanced when Ba2+ replaced Ca2+. 6. Calcium currents of neonatal HMs were characterized in whole-cell patch-clamp recordings of thin medullary slices under conditions that minimized voltage-dependent Na+ and K+ currents. Low voltage-activated (LVA) and a high voltage-activated (HVA) calcium current components were identified on the basis of their voltage thresholds for activation, kinetics of inactivation, and pharmacological sensitivity. 7. The LVA calcium current began to activate at around -60 mV and inactivated nearly completely within 100 ms. Complete steady-state inactivation occurred at potentials more positive than -60 mV. The LVA current was selectively reduced by 1 mM amiloride (31%). 8. A larger-amplitude calcium current activated at potentials around -35 mV. Inactivation of this HVA current was slower than that of the LVA current and incomplete. About 1/3 of this current was sensitive to 1 microM omega-conotoxin GVIA, whereas a smaller fraction was blocked by 10 microM nifedipine.(ABSTRACT TRUNCATED AT 400 WORDS)

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Early Development of Drug-Induced Hepatic Necrosis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100066942 ◽

1971 ◽

Vol 29 ◽

pp. 576-577

Author(s):

F. G. Zaki ◽

E. Detzi ◽

C. H. Keysser

Keyword(s):

Early Development ◽

Hepatic Necrosis ◽

Screening Tests ◽

Dense Matrix ◽

Sprague Dawley ◽

Electron Microscopic ◽

Drug Induced ◽

Hepatocellular Damage ◽

Sprague Dawley Rats ◽

Microscopic Studies

This study represents the first in a series of investigations carried out to elucidate the mechanism(s) of early hepatocellular damage induced by drugs and other related compounds. During screening tests of CNS-active compounds in rats, it has been found that daily oral administration of one of these compounds at a dose level of 40 mg. per kg. of body weight induced diffuse massive hepatic necrosis within 7 weeks in Charles River Sprague Dawley rats of both sexes. Partial hepatectomy enhanced the development of this peculiar type of necrosis (3 weeks instead of 7) while treatment with phenobarbital prior to the administration of the drug delayed the appearance of necrosis but did not reduce its severity.Electron microscopic studies revealed that early development of this liver injury (2 days after the administration of the drug) appeared in the form of small dark osmiophilic vesicles located around the bile canaliculi of all hepatocytes (Fig. 1). These structures differed from the regular microbodies or the pericanalicular multivesicular bodies. They first appeared regularly rounded with electron dense matrix bound with a single membrane. After one week on the drug, these vesicles appeared vacuolated and resembled autophagosomes which soon developed whorls of concentric lamellae or cisterns characteristic of lysosomes (Fig. 2). These lysosomes were found, later on, scattered all over the hepatocytes.

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Patch-Clamp Recording from Human Induced Pluripotent Stem Cell-Derived Cardiomyocytes: Improving Action Potential Characteristics through Dynamic Clamp

International Journal of Molecular Sciences ◽

10.3390/ijms18091873 ◽

2017 ◽

Vol 18 (9) ◽

pp. 1873 ◽

Cited By ~ 23

Author(s):

Arie Verkerk ◽

Christiaan Veerman ◽

Jan Zegers ◽

Isabella Mengarelli ◽

Connie Bezzina ◽

...

Keyword(s):

Stem Cell ◽

Patch Clamp ◽

Action Potential ◽

Pluripotent Stem Cell ◽

Induced Pluripotent Stem Cell ◽

Dynamic Clamp ◽

Patch Clamp Recording ◽

Induced Pluripotent

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Modulating the voltage sensor of a cardiac potassium channel shows antiarrhythmic effects

10.1101/2021.02.25.432939 ◽

2021 ◽

Author(s):

Yangyang Lin ◽

Sam Z. Grinter ◽

Zhongju Lu ◽

Xianjin Xu ◽

Hong Zhan Wang ◽

...

Keyword(s):

Action Potential ◽

In Silico ◽

Therapeutic Efficacy ◽

Torsade De Pointes ◽

Computational Prediction ◽

Chemical Library ◽

Drug Induced ◽

Voltage Dependent ◽

Life Threatening ◽

Approved Drugs

AbstractCardiac arrhythmias are the most common cause of sudden cardiac death worldwide. Lengthening the ventricular action potential duration (APD) either congenitally or via pathologic or pharmacologic means, predisposes to a life-threatening ventricular arrhythmia, Torsade de Pointes. IKs, a slowly activating K+ current plays a role in action potential repolarization. In this study, we screened a chemical library in silico by docking compounds to the voltage sensing domain (VSD) of the IKs channel. Here we show that C28 specifically shifted IKs VSD activation in ventricle to more negative voltages and reversed drug-induced lengthening of APD. At the same dosage, C28 did not cause significant changes of the normal APD in either ventricle or atrium. This study provides evidence in support of a computational prediction of IKs VSD activation as a potential therapeutic approach for all forms of APD prolongation. This outcome could expand the therapeutic efficacy of a myriad of currently approved drugs that may trigger arrhythmias.Significance statementC28, identified by in silico screening, specifically facilitated voltage dependent activation of a cardiac potassium ion channel, IKs. C28 reversed drug-induced prolongation of action potentials, but minimally affected the normal action potential at the same dosage. This outcome supports a computational prediction of modulating IKs activation as a potential therapy for all forms of action potential prolongation, and could expand therapeutic efficacy of many currently approved drugs that may trigger arrhythmias.

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Electrical pacing counteracts intrinsic shortening of action potential duration of neonatal rat ventricular cells in culture

Journal of Molecular and Cellular Cardiology ◽

10.1016/j.yjmcc.2006.06.076 ◽

2006 ◽

Vol 41 (4) ◽

pp. 633-641 ◽

Cited By ~ 38

Author(s):

Alok Sathaye ◽

Nenad Bursac ◽

Sean Sheehy ◽

Leslie Tung

Keyword(s):

Action Potential ◽

Action Potential Duration ◽

Neonatal Rat ◽

Cells In Culture ◽

Ventricular Cells ◽

Electrical Pacing

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Multi-site study of an in vivo phototoxicity evaluation in Sprague-Dawley rats: skin site and sex differences in sensitivity to drug-induced phototoxicity

Fundamental Toxicological Sciences ◽

10.2131/fts.6.171 ◽

2019 ◽

Vol 6 (5) ◽

pp. 171-179 ◽

Cited By ~ 1

Author(s):

Kazuhiro Kuga ◽

Yutaka Yonezawa ◽

Hitoshi Katou

Keyword(s):

Sex Differences ◽

Sprague Dawley ◽

Drug Induced ◽

Skin Site ◽

Sprague Dawley Rats

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Serum Natriuretic Peptides as Differential Biomarkers Allowing for the Distinction between Physiologic and Pathologic Left Ventricular Hypertrophy

Toxicologic Pathology ◽

10.1177/0192623316634231 ◽

2016 ◽

Vol 45 (2) ◽

pp. 344-352 ◽

Cited By ~ 4

Author(s):

Michael E. Dunn ◽

Thomas G. Manfredi ◽

Kevin Agostinucci ◽

Steven K. Engle ◽

Josh Powe ◽

...

Keyword(s):

Cardiac Hypertrophy ◽

Natriuretic Peptide ◽

Natriuretic Peptides ◽

Left Ventricular ◽

Peroxisome Proliferator ◽

Sprague Dawley ◽

Drug Induced ◽

Peroxisome Proliferator Activated Receptor ◽

Sprague Dawley Rats ◽

Exercise Induced

Given the proven utility of natriuretic peptides as serum biomarkers of cardiovascular maladaptation and dysfunction in humans and the high cross-species sequence conservation of atrial natriuretic peptides, natriuretic peptides have the potential to serve as translational biomarkers for the identification of cardiotoxic compounds during multiple phases of drug development. This work evaluated and compared the response of N-terminal proatrial natriuretic peptide (NT-proANP) and N-terminal probrain natriuretic peptide (NT-proBNP) in rats during exercise-induced and drug-induced increases in cardiac mass after chronic swimming or daily oral dosing with a peroxisome proliferator-activated receptor γ agonist. Male Sprague-Dawley rats aged 8 to 10 weeks were assigned to control, active control, swimming, or drug-induced cardiac hypertrophy groups. While the relative heart weights from both the swimming and drug-induced cardiac hypertrophy groups were increased 15% after 28 days of dosing, the serum NT-proANP and NT-proBNP values were only increased in association with cardiac hypertrophy caused by compound administration. Serum natriuretic peptide concentrations did not change in response to adaptive physiologic cardiac hypertrophy induced by a 28-day swimming protocol. These data support the use of natriuretic peptides as fluid biomarkers for the distinction between physiological and drug-induced cardiac hypertrophy.

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Preclinical assessment of tramadol abuse potential: Effects of acute and repeated tramadol on intracranial self-stimulation in rats

Journal of Psychopharmacology ◽

10.1177/0269881120944153 ◽

2020 ◽

Vol 34 (11) ◽

pp. 1316-1325

Author(s):

Ahmad A Altarifi ◽

Megan J Moerke ◽

Mohammad I Alsalem ◽

S Stevens Negus

Keyword(s):

Enzyme Inhibitor ◽

Abuse Potential ◽

Opioid Antagonist ◽

Repeated Treatment ◽

Acute Administration ◽

Sprague Dawley ◽

Drug Induced ◽

Sprague Dawley Rats ◽

Before And After ◽

Self Stimulation

Background: Tramadol is a widely used analgesic that activates mu-opioid receptors (MOR) and inhibits serotonin and norepinephrine transporters. This mixed pharmacology may limit both its own abuse potential and its modulation of abuse potential of other MOR agonists. Aims: This study used an intracranial self-stimulation (ICSS) procedure to compare abuse-related effects produced by acute or repeated treatment with tramadol or morphine in rats. Abuse potential in ICSS procedures is indicated by a drug-induced increase (or ‘facilitation’) of ICSS responding. Methods: Adult male Sprague–Dawley rats were implanted with electrodes targeting the medial forebrain bundle and trained to respond on a lever for pulses of electrical brain stimulation. Tramadol effects were evaluated after acute administration (3.2–32 mg/kg) in the absence or presence of the opioid antagonist naltrexone, the CYP2D6 hepatic-enzyme inhibitor quinine or a combination of both. Additionally, both tramadol and morphine were also tested before and after repeated tramadol (32 mg/kg/day for six days) or repeated morphine (3.2 mg/kg/day for six days). Results: Acute tramadol produced primarily ICSS rate-decreasing effects that were antagonised by naltrexone but not by quinine or naltrexone + quinine. Tramadol also produced little or no ICSS facilitation after repeated tramadol or repeated morphine, and repeated tramadol did not enhance ICSS facilitation by morphine. By contrast, morphine-induced ICSS facilitation was enhanced by repeated morphine treatment. Conclusions: These results suggest that tramadol has lower abuse potential than other abused MOR agonists and that repeated tramadol exposure produces relatively little enhancement of abuse potential of other MOR agonists.

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Abstract 1514: RXP-E: A Connexin43-Binding Peptide that Prevents Action Potential Propagation Block

Circulation ◽

10.1161/circ.118.suppl_18.s_341-a ◽

2008 ◽

Vol 118 (suppl_18) ◽

Author(s):

Rebecca Lewandowski ◽

Kristina Procida ◽

Ravi Vaidyanathan ◽

José Jalife ◽

Morten S Nielsen ◽

...

Keyword(s):

Patch Clamp ◽

Action Potential ◽

Rhode Island ◽

Ventricular Myocytes ◽

Heart Association ◽

Calcium Currents ◽

Neonatal Rat ◽

List Type ◽

Resistance Pathway

Gap junctions (GJ’s) provide a low resistance pathway for cardiac electrical propagation. The role of GJ regulation in arrhythmias is unclear, partly due to the limited availability of pharmacological tools. Recently, we showed that a peptide called “RXP-E” binds to the carboxyl terminal of connexin43 (Cx43) and prevents chemically-induced uncoupling in Cx43-expressing N2a cells. Here, we used pull-down experiments to show that RXP-E binds to adult cardiac Cx43. Patch-clamp studies revealed that RXP-E prevented heptanol-induced and acidification-induced uncoupling in pairs of neonatal rat ventricular myocytes (NRVM’s). Separately, RXP-E was concatenated to a cytoplasmic transduction peptide for translocation into the cytoplasm (construct CTP-RXP-E). The effect of RXP-E on action potential (AP) propagation was assessed by high resolution optical mapping in monolayers of NRVMs, containing approximately 20% of randomly distributed myofibroblasts. Conduction velocity (CV) was 164 ± 8mm/sec (avg±SEM; n=12; pacing frequency 2Hz) in untreated cells, and 158±10mm/sec, (n=6) and 180±7mm/sec (n=10) in monolayers treated with CTP-RXPE or a scrambled version of the peptide (CTP-Scr), respectively (pNS). Exposure of either untreated, or CTP-Scr-treated monolayers to heptanol caused propagation block. However, when heptanol (2 mmol/L) was added to the superfusate of monolayers loaded with CTP-RXP-E, AP propagation was maintained, albeit at a slower velocity (87±5mm/sec;n=4; P<0.001). Similarly, intracellular acidification (pHi=6.2) caused a loss of AP propagation in control or CTP-Scr monolayers; however, propagation was maintained in CTP-RXP-E treated cells, though at a slower rate (CV=93 ± 28mm/sec; n=4). Consistent with these results, patch clamp experiments revealed that RXP-E did not prevent heptanol-induced block of sodium or calcium currents, nor did it alter the voltage dependence or amplitude of Kir2.1/Kir2.3 currents. RXP-E is the first synthetic molecule known to: bind cardiac Cx43; prevent heptanol and acidification-induced uncoupling of cardiac GJ’s and preserve AP propagation among cardiac myocytes. RXP-E can be used to characterize the role of GJ’s in the function of multicellular systems, including the heart. This research has received full or partial funding support from the American Heart Association, AHA Founders Affiliate (Connecticut, Maine, Massachusetts, New Hampshire, New Jersey, New York, Rhode Island, Vermont).

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