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Kim HJ, Li M, Erlich EC, Randolph GJ, Davis MJ. ERG K + channels mediate a major component of action potential repolarization in lymphatic muscle. Sci Rep 2023; 13:14890. [PMID: 37689781 PMCID: PMC10492848 DOI: 10.1038/s41598-023-41995-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Accepted: 09/04/2023] [Indexed: 09/11/2023] Open
Abstract
Smooth muscle cells in the walls of collecting lymphatic vessels fire spontaneous action potentials (APs), which conduct rapidly over the muscle layer to initiate contractions that propel lymph. Several ion channels have been implicated in the currents underlying the AP spike and the preceding diastolic depolarization, but the molecular identities of K+ channels involved in AP repolarization are unknown. Based on previous studies of other rhythmically active smooth muscles, we hypothesized that ether-a-go-go related gene (ERG) K+ channels (Kv11) play an important role in repolarization of the AP in lymphatic muscle. Message for one or more ERG channel isoforms was detected by RT-PCR analysis of lymphatic vessels from mice, rats and humans. Membrane potential recordings in smooth muscle cells of rat and human lymphatics revealed that nanomolar concentrations of ERG-1 inhibitors (E-4031 and BeKm-1) prolonged the duration of the AP plateau (normally ~ 1 s in duration) and induced multiple spikes, whereas ERG-1 activators (ICA-105574 and RPR-260243) shortened the plateau and could completely inhibit spontaneous APs. At relatively high inhibitor concentrations, the AP plateau duration lasted as long as 24 s. ERG activators reversed the effects of ERG inhibitors and vice-versa. In pressure myograph studies, ERG channel inhibition prolonged the diastolic repolarization phase of the contraction cycle and reduced the frequency of spontaneous contractions. This is the first evidence for a specific K+ channel contributing to the AP in lymphatic muscle. Our results imply that lymphatic contractile dysfunction may occur in long QT type II patients with mutations that result in ERG channel loss-of-function or impaired trafficking of the channel to the cell membrane.
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Affiliation(s)
- Hae Jin Kim
- Department of Medical Pharmacology & Physiology, University of Missouri, One Hospital Drive, MA415 Medical Sciences Building, Columbia, MO, 65212, USA
| | - Min Li
- Department of Medical Pharmacology & Physiology, University of Missouri, One Hospital Drive, MA415 Medical Sciences Building, Columbia, MO, 65212, USA
| | - Emma C Erlich
- Department of Pathology and Immunology, Washington University, St Louis, MO, USA
| | - Gwendalyn J Randolph
- Department of Pathology and Immunology, Washington University, St Louis, MO, USA
| | - Michael J Davis
- Department of Medical Pharmacology & Physiology, University of Missouri, One Hospital Drive, MA415 Medical Sciences Building, Columbia, MO, 65212, USA.
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2
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Barrese V, Wehbe Z, Linden A, McDowell S, Forrester E, Povstyan O, McCloskey KD, Greenwood IA. Key role for Kv11.1 (ether-a-go-go related gene) channels in rat bladder contractility. Physiol Rep 2023; 11:e15583. [PMID: 36750122 PMCID: PMC9904964 DOI: 10.14814/phy2.15583] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Revised: 01/04/2023] [Accepted: 01/04/2023] [Indexed: 06/01/2023] Open
Abstract
In addition, to their established role in cardiac myocytes and neurons, ion channels encoded by ether-a-go-go-related genes (ERG1-3 or kcnh2,3 and 6) (kcnh2) are functionally relevant in phasic smooth muscle. The aim of the study was to determine the expression and functional impact of ERG expression products in rat urinary bladder smooth muscle using quantitative polymerase chain reaction, immunocytochemistry, whole-cell patch-clamp and isometric tension recording. kcnh2 was expressed in rat bladder, whereas kcnh6 and kcnh3 expression were negligible. Immunofluorescence for the kcnh2 expression product Kv11.1 was detected in the membrane of isolated smooth muscle cells. Potassium currents with voltage-dependent characteristics consistent with Kv11.1 channels and sensitive to the specific blocker E4031 (1 μM) were recorded from isolated detrusor smooth muscles. Disabling Kv11.1 activity with specific blockers (E4031 and dofetilide, 0.2-20 μM) augmented spontaneous contractions to a greater extent than BKCa channel blockers, enhanced carbachol-driven activity, increased nerve stimulation-mediated contractions, and impaired β-adrenoceptor-mediated inhibitory responses. These data establish for the first time that Kv11.1 channels are key determinants of contractility in rat detrusor smooth muscle.
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Affiliation(s)
- Vincenzo Barrese
- Vascular Biology Research CentreMolecular and Clinical Sciences Research Institute, St George's University of LondonLondonUK
- Department of Neuroscience, Reproductive Sciences and DentistryUniversity of Naples Federico IINaplesItaly
| | - Zena Wehbe
- Vascular Biology Research CentreMolecular and Clinical Sciences Research Institute, St George's University of LondonLondonUK
| | - Alice Linden
- Vascular Biology Research CentreMolecular and Clinical Sciences Research Institute, St George's University of LondonLondonUK
| | - Sarah McDowell
- Patrick G. Johnston Centre for Cancer Research, School of Medicine, Dentistry and Biomedical SciencesQueen's University BelfastBelfastUK
| | - Elizabeth Forrester
- Vascular Biology Research CentreMolecular and Clinical Sciences Research Institute, St George's University of LondonLondonUK
| | | | - Karen D. McCloskey
- Patrick G. Johnston Centre for Cancer Research, School of Medicine, Dentistry and Biomedical SciencesQueen's University BelfastBelfastUK
| | - Iain A. Greenwood
- Vascular Biology Research CentreMolecular and Clinical Sciences Research Institute, St George's University of LondonLondonUK
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Ocampo L, Coello M, Aquino I. Comparative Efficacy of the Prokinetic Effects of Cisapride and Tegaserod in Equines. J Equine Vet Sci 2020; 92:103179. [PMID: 32797801 DOI: 10.1016/j.jevs.2020.103179] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Revised: 05/23/2020] [Accepted: 06/23/2020] [Indexed: 11/25/2022]
Abstract
The aim of this study was to compare the effects of cisapride and tegaserod on intestinal smooth muscle activity in equines. Efficacy was evaluated through measurement of gastrointestinal transit time, bowel movements per day, stool weight, and bowel sounds. Drug safety was evaluated via heart rate, respiratory rate, and rectal temperature. Records were obtained throughout three periods: a control phase without treatment, a period of cisapride administration at a dose of 0.22 mg/kg, and a period of tegaserod treatment at a dose of 0.27 mg/kg. Gastrointestinal transit time, bowel movements per day, and stool weight were significantly improved on administration of both cisapride and tegaserod, as compared with the control phase. With tegaserod administration, gastrointestinal transit time accelerates more than to cisapride administration; however, no significant difference was seen in bowel movements per day and stool weight. In terms of heart rate, respiratory rate, and rectal temperature, no significant variations were seen between the three sample phases. Because of the above findings, tegaserod can be considered an effective stimulant of intestinal smooth muscle, accelerating gastrointestinal transit time in healthy horses and representing a potential therapeutic agent similar to cisapride.
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Affiliation(s)
- Luis Ocampo
- Physiology and Pharmacology Department. School of Veterinary Medicine and Animal Science, National Autonomous University of Mexico, Mexico City, Mexico
| | - María Coello
- Department of Medicine, Surgery, and Husbandry for Horses. School of Veterinary Medicine and Animal Science, National Autonomous University of Mexico, Mexico City, Mexico
| | - Itzcoatl Aquino
- Physiology and Pharmacology Department. School of Veterinary Medicine and Animal Science, National Autonomous University of Mexico, Mexico City, Mexico.
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4
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The Regulation of Uterine Function During Parturition: an Update and Recent Advances. Reprod Sci 2020; 27:3-28. [DOI: 10.1007/s43032-019-00001-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2017] [Accepted: 03/19/2019] [Indexed: 12/13/2022]
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5
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Shults NV, Rybka V, Suzuki YJ, Brelidze TI. Increased Smooth Muscle Kv11.1 Channel Expression in Pulmonary Hypertension and Protective Role of Kv11.1 Channel Blocker Dofetilide. THE AMERICAN JOURNAL OF PATHOLOGY 2020; 190:48-56. [PMID: 31839145 PMCID: PMC6943378 DOI: 10.1016/j.ajpath.2019.09.010] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Revised: 09/05/2019] [Accepted: 09/17/2019] [Indexed: 01/08/2023]
Abstract
Kv11.1 potassium channels are essential for heart repolarization. Prescription medication that blocks Kv11.1 channels lengthens the ventricular action potential and causes cardiac arrhythmias. Surprisingly little is known about the Kv11.1 channel expression and function in the lung tissue. Here we report that Kv11.1 channels were abundantly expressed in the large pulmonary arteries (PAs) of healthy lung tissues from humans and rats. Kv11.1 channel expression was increased in the lungs of humans affected by chronic obstructive pulmonary disease-associated pulmonary hypertension and in the lungs of rats with pulmonary arterial hypertension (PAH). In healthy lung tissues from humans and rats, Kv11.1 channels were confined to the large PAs. In humans with chronic obstructive pulmonary disease-associated pulmonary hypertension and in rats with PAH, Kv11.1 channels were expressed in both the large and small PAs. The increase in Kv11.1 channel expression closely followed the time-course of the development of pulmonary vascular remodeling in PAH rats. Treatment of PAH rats with dofetilide, an Kv11.1 channel blocker approved by the US Food and Drug Administration for use in the treatment of arrythmia, inhibited PAH-associated pulmonary vascular remodeling. Taken together, the findings from this study uncovered a novel role of Kv11.1 channels in lung function and their potential as new drug targets in the treatment of pulmonary hypertension. The protective effect of dofetilide raises the possibility of repurposing this antiarrhythmic drug for the treatment of patients with pulmonary hypertension.
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MESH Headings
- Adult
- Aged
- Aged, 80 and over
- Animals
- Arrhythmias, Cardiac/etiology
- Arrhythmias, Cardiac/pathology
- Arrhythmias, Cardiac/prevention & control
- Case-Control Studies
- ERG1 Potassium Channel/antagonists & inhibitors
- ERG1 Potassium Channel/metabolism
- Female
- Follow-Up Studies
- Humans
- Male
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/metabolism
- Muscle, Smooth, Vascular/pathology
- Phenethylamines/pharmacology
- Potassium Channel Blockers/pharmacology
- Prognosis
- Pulmonary Arterial Hypertension/complications
- Pulmonary Arterial Hypertension/metabolism
- Pulmonary Arterial Hypertension/pathology
- Rats, Sprague-Dawley
- Sulfonamides/pharmacology
- Vascular Remodeling/drug effects
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Affiliation(s)
- Nataliia V Shults
- Department of Pharmacology and Physiology, Georgetown University Medical Center, Washington, District of Columbia
| | - Vladyslava Rybka
- Department of Pharmacology and Physiology, Georgetown University Medical Center, Washington, District of Columbia
| | - Yuichiro J Suzuki
- Department of Pharmacology and Physiology, Georgetown University Medical Center, Washington, District of Columbia
| | - Tinatin I Brelidze
- Department of Pharmacology and Physiology, Georgetown University Medical Center, Washington, District of Columbia.
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Lefebvre RA, Callens C, Van Colen I, Delesalle CJG. The 5-HT 4 receptor agonist prucalopride does not facilitate cholinergic neurotransmission in circular and longitudinal smooth muscle preparations of equine mid-jejunum. Res Vet Sci 2017; 114:153-162. [PMID: 28419939 DOI: 10.1016/j.rvsc.2017.04.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Revised: 03/10/2017] [Accepted: 04/07/2017] [Indexed: 12/31/2022]
Abstract
BACKGROUND Postoperative ileus (POI) remains an important cause of death in horses. The recently developed selective 5-HT4 receptor agonists such as prucalopride target 5-HT4 receptors on myenteric cholinergic neurons to enhance acetylcholine release and GI motility. No clearcut in vitro evaluation whether highly selective 5-HT4 receptor agonists enhance submaximal cholinergic neurotransmission towards the muscle layer has been performed in horses. OBJECTIVES To identify functional 5-HT4 receptors in equine jejunum. STUDY DESIGN In vitro experimental study. METHODS Circular and longitudinal smooth muscle strips (mid-jejunum) were mounted in organ baths between 2 platinum electrodes allowing electrical field stimulation (EFS). To delineate the conditions to obtain purely cholinergic responses, voltage-response curves were studied. To investigate the influence of prucalopride and 5-HT, submaximal cholinergic contractions at a single voltage were induced. RESULTS In circular and longitudinal strips, EFS induced voltage-dependent neurogenic on-contractions when the bathing medium contained a NO-synthesis inhibitor and apamin to prevent inhibitory responses to NO and ATP. Contractions at a voltage inducing 50% of maximal amplitude were cholinergic, as they were blocked by atropine. These contractions were not influenced by prucalopride (up to 3μM), even in the presence of the phosphodiesterase inhibitor isobutyl-methyl-xanthine to inhibit breakdown of the second messenger of 5-HT4 receptors, cAMP. Also the full 5-HT4 receptor agonist 5-HT did not influence the EFS-induced submaximal cholinergic contractions. Moreover, prucalopride did not influence muscle tone continuously enhanced with KCl. CONCLUSIONS There are no functional 5-HT4 receptors on myenteric cholinergic neurons nor muscular 5-HT4 receptors in equine jejunum.
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Affiliation(s)
- Romain Adelin Lefebvre
- Heymans Institute of Pharmacology, Faculty of Medicine and Health Sciences, De Pintelaan 185, B-9000 Gent, Belgium
| | - Chana Callens
- Department of Industrial Biological Sciences-Kortrijk, Faculty of Bioscience Engineering, Graaf Karel de Goedelaan 5, 8500 Kortrijk, Belgium
| | - Inge Van Colen
- Heymans Institute of Pharmacology, Faculty of Medicine and Health Sciences, De Pintelaan 185, B-9000 Gent, Belgium
| | - Catherine John Ghislaine Delesalle
- Department of Comparative Physiology and Biometrics, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820 Merelbeke, Belgium.
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7
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Laus F, Fratini M, Paggi E, Faillace V, Spaterna A, Tesei B, Fettucciari K, Bassotti G. Effects of Single-Dose Prucalopride on Intestinal Hypomotility in Horses: Preliminary Observations. Sci Rep 2017; 7:41526. [PMID: 28128322 PMCID: PMC5269739 DOI: 10.1038/srep41526] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Accepted: 12/21/2016] [Indexed: 11/08/2022] Open
Abstract
Abnormalities of gastrointestinal motility are often a challenge in horses; however, the use of prokinetic drugs in such conditions must be firmly established yet. For this reason we carried out a preliminary study on the effects of prucalopride on intestinal motor activity of horses with gut hypomotility. The effect of prucalopride per os by oral dose syringe (2 mg/100 kg body weight) was assessed by abdominal ultrasound (evaluating duodenal, cecal, and colonic motor activity) in six horses with gut hypomotility. After administration of prucalopride, a significant increase of contractile activity was found in the duodenum at 30 minutes (p = 0.0005), 60 minutes (p = 0.01) and 90 minutes (p = 0.01), whereas in the cecum and in the left colon the increase was only present at 60 minutes (p = 0.03, and p = 0.02, respectively). No changes from baseline heart and respiratory rate or behavior side effects were observed after administration of the drug and throughout the observation period. Prucalopride may be a useful adjunct to the therapeutic armamentary for treating hypomotile upper gut conditions of horses. Dosing information is however needed to establish its actual clinical efficacy and its proper effects on the large bowel in these animals.
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Affiliation(s)
- Fulvio Laus
- School of Bioscences and Veterinary Medicine, University of Camerino, Via Circonvallazione 63/95, 62024 Matelica, Italy
| | - Margherita Fratini
- School of Bioscences and Veterinary Medicine, University of Camerino, Via Circonvallazione 63/95, 62024 Matelica, Italy
| | - Emanuele Paggi
- School of Bioscences and Veterinary Medicine, University of Camerino, Via Circonvallazione 63/95, 62024 Matelica, Italy
| | - Vanessa Faillace
- School of Bioscences and Veterinary Medicine, University of Camerino, Via Circonvallazione 63/95, 62024 Matelica, Italy
| | - Andrea Spaterna
- School of Bioscences and Veterinary Medicine, University of Camerino, Via Circonvallazione 63/95, 62024 Matelica, Italy
| | - Beniamino Tesei
- School of Bioscences and Veterinary Medicine, University of Camerino, Via Circonvallazione 63/95, 62024 Matelica, Italy
| | - Katia Fettucciari
- Department of Experimental Medicine, Perugia University School of Medicine, Piazzale Lucio Severi, 1, 06159 San Sisto (Perugia), Italy
| | - Gabrio Bassotti
- Department of Medicine, Perugia University School of Medicine, Piazzale Lucio Severi, 1, 06159 San Sisto (Perugia), Italy
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8
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Nieto JE, Morales B, Yamout SZ, Stanley SD, Harmon FA, Snyder JR. In vivo and in vitro effects of neostigmine on gastrointestinal tract motility of horses. Am J Vet Res 2013; 74:579-88. [PMID: 23531066 DOI: 10.2460/ajvr.74.4.579] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To determine the response to neostigmine of the contractile activity of the jejunum and pelvic flexure and the effects of a continuous rate infusion (CRI) of neostigmine in horses. ANIMALS 7 adult horses and tissue from 12 adult horses. PROCEDURES A CRI of neostigmine (0.008 mg/kg/h) or placebo was administered to 6 horses in a crossover study design. Gastric emptying was evaluated by the acetaminophen test. The frequency of defecation and urination and the consistency and weight of feces were recorded throughout the experiment. The effect of neostigmine on smooth muscle contractile activity was evaluated in tissues from the jejunum and pelvic flexure. The effect of neostigmine and acetylcholine after incubation with muscarinic receptor antagonists (atropine and DAU 5884) and an acetylcholinesterase inhibitor (edrophonium) was also investigated in vitro. RESULTS No difference was observed between neostigmine and placebo for time to reach peak plasma acetaminophen concentration and absorption rate constant. A CRI of neostigmine increased fecal production and frequency of urination. Neostigmine induced a dose-dependent increase of contractile amplitude in jejunum and pelvic flexure muscle strips. Incubation of muscle strips with atropine and DAU 5884 inhibited the response to acetylcholine and neostigmine. Incubation of smooth muscle strips from the jejunum with edrophonium increased the response to acetylcholine and had no effect on the response to neostigmine in vitro. CONCLUSIONS AND CLINICAL RELEVANCE A CRI of neostigmine increased fecal production and urination frequency in horses. A CRI of neostigmine did not decrease gastric emptying. Neostigmine stimulated contractile activity of jejunum and pelvic flexure smooth muscle strips in vitro.
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Affiliation(s)
- Jorge E Nieto
- Comparative Gastrointestinal Laboratory, Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California-Davis, Davis, CA 95616, USA.
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9
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Vandenberg JI, Perry MD, Perrin MJ, Mann SA, Ke Y, Hill AP. hERG K+ Channels: Structure, Function, and Clinical Significance. Physiol Rev 2012; 92:1393-478. [DOI: 10.1152/physrev.00036.2011] [Citation(s) in RCA: 463] [Impact Index Per Article: 38.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
The human ether-a-go-go related gene (hERG) encodes the pore-forming subunit of the rapid component of the delayed rectifier K+ channel, Kv11.1, which are expressed in the heart, various brain regions, smooth muscle cells, endocrine cells, and a wide range of tumor cell lines. However, it is the role that Kv11.1 channels play in the heart that has been best characterized, for two main reasons. First, it is the gene product involved in chromosome 7-associated long QT syndrome (LQTS), an inherited disorder associated with a markedly increased risk of ventricular arrhythmias and sudden cardiac death. Second, blockade of Kv11.1, by a wide range of prescription medications, causes drug-induced QT prolongation with an increase in risk of sudden cardiac arrest. In the first part of this review, the properties of Kv11.1 channels, including biogenesis, trafficking, gating, and pharmacology are discussed, while the second part focuses on the pathophysiology of Kv11.1 channels.
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Affiliation(s)
- Jamie I. Vandenberg
- Mark Cowley Lidwill Research Programme in Cardiac Electrophysiology, Victor Chang Cardiac Research Institute, Sydney, New South Wales, Australia; St Vincent's Clinical School, University of New South Wales, New South Wales, Australia; and University of Ottawa Heart Institute, Ottawa, Canada
| | - Matthew D. Perry
- Mark Cowley Lidwill Research Programme in Cardiac Electrophysiology, Victor Chang Cardiac Research Institute, Sydney, New South Wales, Australia; St Vincent's Clinical School, University of New South Wales, New South Wales, Australia; and University of Ottawa Heart Institute, Ottawa, Canada
| | - Mark J. Perrin
- Mark Cowley Lidwill Research Programme in Cardiac Electrophysiology, Victor Chang Cardiac Research Institute, Sydney, New South Wales, Australia; St Vincent's Clinical School, University of New South Wales, New South Wales, Australia; and University of Ottawa Heart Institute, Ottawa, Canada
| | - Stefan A. Mann
- Mark Cowley Lidwill Research Programme in Cardiac Electrophysiology, Victor Chang Cardiac Research Institute, Sydney, New South Wales, Australia; St Vincent's Clinical School, University of New South Wales, New South Wales, Australia; and University of Ottawa Heart Institute, Ottawa, Canada
| | - Ying Ke
- Mark Cowley Lidwill Research Programme in Cardiac Electrophysiology, Victor Chang Cardiac Research Institute, Sydney, New South Wales, Australia; St Vincent's Clinical School, University of New South Wales, New South Wales, Australia; and University of Ottawa Heart Institute, Ottawa, Canada
| | - Adam P. Hill
- Mark Cowley Lidwill Research Programme in Cardiac Electrophysiology, Victor Chang Cardiac Research Institute, Sydney, New South Wales, Australia; St Vincent's Clinical School, University of New South Wales, New South Wales, Australia; and University of Ottawa Heart Institute, Ottawa, Canada
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10
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Jang SY, Ju EY, Kim DE, Kim JH, Kim YH, Son M, Jang M, Jeong JH, Kim KS. First flatus time and xerostomia associated with gum-chewing after liver resection. J Clin Nurs 2012; 21:2188-92. [PMID: 22672009 DOI: 10.1111/j.1365-2702.2012.04132.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
AIMS AND OBJECTIVES The aim of this study was to compare the return of bowel function and xerostomia in patients who were and were not instructed to chew gum after elective open liver resection. BACKGROUND Patients who undergo liver resection have limited early ambulation, because they require bed rest after surgery to prevent internal bleeding. They normally also require narcotic analgesics or patient-controlled analgesia for pain control. For these reasons, they often have symptoms of intestinal gas accumulation, abdominal distension and/or abdominal pain. DESIGN Prospective case-control study. METHODS Forty-two patients with hepatocellular carcinoma who were treated at Samsung Medical Center from September 2010 to February 2011 were included in this study. Patients who were scheduled for elective liver resection for hepatocellular carcinoma and were over 30 years of age were eligible. Patients were assigned to a gum-chewing group or a non-gum-chewing (control) group before surgery. RESULTS The mean age of the gum-chewing group was 54·9 (±9·7) years, and the mean age of the control group was 55·1 (±8·4) years. The mean values of first flatus time and xerostomia were higher in the control group than in the gum-chewing group. First flatus time and xerostomia grade were significantly decreased in gum-chewing group compared with the control group after adjustment for hospitalisation days, duration of surgery and amount of analgesics administered. CONCLUSION Patients who were instructed to chew gum after surgery demonstrated faster bowel function recovery and lower xerostomia grade after elective open liver resection than patients who did not chew gum. RELEVANCE TO CLINICAL PRACTICE Gum-chewing is an inexpensive, helpful adjunct to standard postoperative care after liver resection.
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Affiliation(s)
- Shin Yi Jang
- Cardiovascular Imaging Center, Samsung Medical Center, Seoul, Korea
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11
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Expression and immunolocalization of ERG1 potassium channels in the rat kidney. Histochem Cell Biol 2009; 133:189-99. [DOI: 10.1007/s00418-009-0658-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/23/2009] [Indexed: 10/20/2022]
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12
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Greenwood IA, Yeung SY, Tribe RM, Ohya S. Loss of functional K+ channels encoded by ether-à-go-go-related genes in mouse myometrium prior to labour onset. J Physiol 2009; 587:2313-26. [PMID: 19332483 DOI: 10.1113/jphysiol.2009.171272] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
There is a growing appreciation that ion channels encoded by the ether-à-go-go-related gene family have a functional impact in smooth muscle in addition to their accepted role in cardiac myocytes and neurones. This study aimed to assess the expression of ERG1-3 (KCNH1-3) genes in the murine myometrium (smooth muscle layer of the uterus) and determine the functional impact of the ion channels encoded by these genes in pregnant and non-pregnant animals. Quantitative RT-PCR did not detect message for ERG2 and 3 in whole myometrial tissue extracts. In contrast, message for two isoforms of mERG1 were readily detected with mERG1a more abundant than mERG1b. In isometric tension studies of non-pregnant myometrium, the ERG channel blockers dofetilide (1 microM), E4031 (1 microM) and Be-KM1 (100 nM) increased spontaneous contractility and ERG activators (PD118057 and NS1643) inhibited spontaneous contractility. In contrast, neither ERG blockade nor activation had any effect on the inherent contractility in myometrium from late pregnant (19 days gestation) animals. Moreover, dofetilide-sensitive K(+) currents with distinctive 'hooked' kinetics were considerably smaller in uterine myocytes from late pregnant compared to non-pregnant animals. Expression of mERG1 isoforms did not alter throughout gestation or upon delivery, but the expression of genes encoding auxillary subunits (KCNE) were up-regulated considerably. This study provides the first evidence for a regulation of ERG-encoded K(+) channels as a precursor to late pregnancy physiological activity.
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Affiliation(s)
- I A Greenwood
- Division of Basic Medical Sciences, Ion Channels And Cell Signaling Research Centre, St George's, University of London, London SW17 0RE, UK.
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13
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Okamura K, Sasaki N, Yamada M, Yamada H, Inokuma H. Effects of mosapride citrate, metoclopramide hydrochloride, lidocaine hydrochloride, and cisapride citrate on equine gastric emptying, small intestinal and caecal motility. Res Vet Sci 2008; 86:302-8. [PMID: 18723200 DOI: 10.1016/j.rvsc.2008.07.008] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2008] [Revised: 06/05/2008] [Accepted: 07/11/2008] [Indexed: 12/14/2022]
Abstract
OBJECTIVE Although extensive work has been done to elucidate the beneficial and unfavorable effects of gastrointestinal prokinetic agents in humans, little is known on the effects of these agents in horses. In this study, we compared the effects of mosapride, metoclopramide, cisapride, and lidocaine on equine gastric emptying, jejunal and caecal motility and evaluated these agents' adverse drug reactions (ADRs). ANIMALS Seven healthy adult Thoroughbreds. PROCEDURE Mosapride 1.0mg/kg and 2.0mg/kg, metoclopramide 0.2mg/kg, and cisapride 1.0mg/kg were dissolved in 100mL distilled water for oral administration. Lidocaine 1.3mg/kg was mixed with 500 mL saline for a 30-min intravenous infusion. Oral administration of 100mL distilled water was used as control. Gastric emptying was evaluated using (13)CO(2) breath test, and jejunal and caecal motility was assessed by electrointestinography. RESULTS The present study demonstrates that mosapride at doses of 1.0mg/kg and 2.0mg/kg facilitates gastric emptying in horses. Improved jejunal motility was observed following administration of mosapride (1.0mg/kg and 2.0mg/kg), metoclopramide (0.2mg/kg), and cisapride (1.0mg/kg). Similarly, improved caecal motility was observed following administration of mosapride (2.0mg/kg). CONCLUSIONS AND CLINICAL RELEVANCE This study shows that among the prokinetic agents studied here, only mosapride (2.0mg/kg) promotes jejunal and caecal motility in horses. Considering mosapride ADRs profile, it is believed that this compound is useful in the treatment of diseases associated with decreased GI motility, including postoperative ileus.
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Affiliation(s)
- Koichi Okamura
- United Graduate School of Veterinary Sciences, Gifu University, 1-1 Yanago, Gifu-shi 501-1193, Japan
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Mewe M, Wulfsen I, Schuster AME, Middendorff R, Glassmeier G, Schwarz JR, Bauer CK. Erg K+ channels modulate contractile activity in the bovine epididymal duct. Am J Physiol Regul Integr Comp Physiol 2008; 294:R895-904. [PMID: 18184764 DOI: 10.1152/ajpregu.00521.2007] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The expression and functional role of ether-à-go-go-related gene (erg) K+ channels were examined in the bovine epididymal duct. Sperm transit through the epididymal duct relies on spontaneous phasic contractions (SC) of the peritubular smooth muscle wall. Isometric tension studies revealed SC-enhancing effects of the erg channel blockers E-4031, dofetilide, cisapride, and haloperidol and SC-suppressing effects of the activator NS-1643. In the corpus epididymidis, EC50 values of 32 nM and 8.3 microM were determined for E-4031 and NS-1643, respectively. E-4031 was also able to elicit contraction in epithelium-denuded corpus segments, which lacked SC. In the cauda region, E-4031 and NS-1643 exerted effects on agonist-induced contraction similar to those observed in the proximal duct. Experiments with nifedipine and thapsigargin suggested that the excitatory effects of E-4031 depended mainly on external calcium influx and not on intracellular calcium release. Western blot and RT-PCR assays revealed the expression of both, erg1a and erg1b, in all duct regions. Because erg1b appears to predominate in the epididymal duct, patch-clamp experiments were performed on heterologously expressed erg1b channels to investigate the sensitivity of this splice variant to NS-1643. In contrast to its effects on erg1a, NS-1643 induced a concentration-dependent current increase mainly due to a marked leftward shift in erg1b channel activation by approximately 30 mV at 10 microM, explaining the inhibitory effect of the drug on epididymal SC. In summary, these data provide strong evidence for a physiological role of erg1 channels in regulating epididymal motility patterns.
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Affiliation(s)
- Marco Mewe
- Institute of Vegetative Physiology and Pathophysiology, University Medical Center, Hamburg-Eppendorf, Hamburg, Germany.
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Yeung SYM, Greenwood IA. Pharmacological and biophysical isolation of K+ currents encoded by ether-à-go-go-related genes in murine hepatic portal vein smooth muscle cells. Am J Physiol Cell Physiol 2006; 292:C468-76. [PMID: 16870833 DOI: 10.1152/ajpcell.00142.2006] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Previous studies have shown that murine portal vein myocytes express ether-à-go-go related genes (ERGs) and exhibit distinctive currents when recorded under symmetrical K(+) conditions. The aim of the present study was to characterize ERG channel currents evoked from a negative holding potential under conditions more pertinent to a physiological scenario to assess the possible functional impact of this conductance. Currents were recorded with ruptured or perforated patch variants of the whole cell technique from a holding potential of -60 mV. Application of three structurally distinct and selective ERG channel blockers, E-4031, dofetilide, and the peptide toxin BeKM-1, all inhibited a significant proportion of the outward current and abolished inward currents with distinctive "hooked" kinetics recorded on repolarization. Dofetilide-sensitive currents at negative potentials evoked by depolarization to +40 mV had a voltage-dependent time to peak and rate of decay characteristic of ERG channels. Application of the novel ERG channel activator PD-118057 (1-10 microM) markedly enhanced the hooked inward currents evoked by membrane depolarization and hyperpolarized the resting membrane potential recorded by current clamp and the perforated patch configuration by approximately 20 mV. In contrast, ERG channel blockade by dofetilide (1 microM) depolarized the resting membrane potential by approximately 8 mV. These data are the first record of ERG channel currents in smooth muscle cells under quasi-physiological conditions that suggest that ERG channels contribute to the resting membrane potential in these cells.
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Affiliation(s)
- Shuk Yin M Yeung
- Division of Basic Medical Sciences, Ion Channels and Cell Signalling Research Centre, St. George's, University of London, London SW17 0RE, UK
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