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Jackson SJ, Authier S, Brohmann H, Goody SM, Jones D, Prior H, Rosch A, Traebert M, Tse K, Valentin JP, Milne A. Neurofunctional test batteries in safety pharmacology – Current and emerging considerations for the drug development process. J Pharmacol Toxicol Methods 2019; 100:106602. [DOI: 10.1016/j.vascn.2019.106602] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Revised: 06/18/2019] [Accepted: 06/20/2019] [Indexed: 12/16/2022]
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2
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Acierno MJ, Brown S, Coleman AE, Jepson RE, Papich M, Stepien RL, Syme HM. ACVIM consensus statement: Guidelines for the identification, evaluation, and management of systemic hypertension in dogs and cats. J Vet Intern Med 2018; 32:1803-1822. [PMID: 30353952 PMCID: PMC6271319 DOI: 10.1111/jvim.15331] [Citation(s) in RCA: 262] [Impact Index Per Article: 43.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Accepted: 08/29/2018] [Indexed: 12/12/2022] Open
Abstract
An update to the 2007 American College of Veterinary Internal Medicine (ACVIM) consensus statement on the identification, evaluation, and management of systemic hypertension in dogs and cats was presented at the 2017 ACVIM Forum in National Harbor, MD. The updated consensus statement is presented here. The consensus statement aims to provide guidance on appropriate diagnosis and treatment of hypertension in dogs and cats.
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Affiliation(s)
- Mark J Acierno
- Department of Medicine, College of Veterinary Medicine, Midwestern University, 5715 W. Utopia Rd, Glendale Arizona 85308
| | - Scott Brown
- College of Veterinary Medicine, University of Georgia, Athens, Georgia
| | - Amanda E Coleman
- College of Veterinary Medicine, University of Georgia, Athens, Georgia
| | - Rosanne E Jepson
- Department of Clinical Science and Services, Royal Veterinary College, London, United Kingdom
| | - Mark Papich
- College of Veterinary Medicine, North Carolina State University, Raleigh, North Carolina
| | - Rebecca L Stepien
- Department of Medical Sciences, University of Wisconsin School of Veterinary Medicine, Madison, Wisconsin
| | - Harriet M Syme
- Department of Clinical Science and Services, Royal Veterinary College, London, United Kingdom
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3
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Affiliation(s)
- Mary Ellen Goldberg
- Academy of Laboratory Animal Veterinary Technicians and Nurses
- Organizing Committee Academy of Physical Rehabilitation Veterinary Technicians
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Joo YS, Lee HJ, Choi JS, Sung KW. Acepromazine inhibits hERG potassium ion channels expressed in human embryonic kidney 293 cells. THE KOREAN JOURNAL OF PHYSIOLOGY & PHARMACOLOGY : OFFICIAL JOURNAL OF THE KOREAN PHYSIOLOGICAL SOCIETY AND THE KOREAN SOCIETY OF PHARMACOLOGY 2017; 21:75-82. [PMID: 28066143 PMCID: PMC5214913 DOI: 10.4196/kjpp.2017.21.1.75] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/18/2016] [Revised: 09/07/2016] [Accepted: 09/09/2016] [Indexed: 12/22/2022]
Abstract
The effects of acepromazine on human ether-à-go-go-related gene (hERG) potassium channels were investigated using whole-cell voltage-clamp technique in human embryonic kidney (HEK293) cells transfected with hERG. The hERG currents were recorded with or without acepromazine, and the steady-state and peak tail currents were analyzed for the evaluating the drug effects. Acepromazine inhibited the hERG currents in a concentration-dependent manner with an IC50 value of 1.5 µM and Hill coefficient of 1.1. Acepromazine blocked hERG currents in a voltage-dependent manner between –40 and +10 mV. Before and after application of acepromazine, the half activation potentials of hERG currents changed to hyperpolarizing direction. Acepromazine blocked both the steady-state hERG currents by depolarizing pulse and the peak tail currents by repolarizing pulse; however, the extent of blocking by acepromazine in the repolarizing pulse was more profound than that in the depolarizing pulse, indicating that acepromazine has a high affinity for the open state of the channels, with a relatively lower affinity for the closed state of hERG channels. A fast application of acepromazine during the tail currents inhibited the open state of hERG channels in a concentration-dependent. The steady-state inactivation of hERG currents shifted to the hyperpolarized direction by acepromazine. These results suggest that acepromazine inhibits the hERG channels probably by an open- and inactivated-channel blocking mechanism. Regarding to the fact that the hERG channels are the potential target of drug-induced long QT syndrome, our results suggest that acepromazine can possibly induce a cardiac arrhythmia through the inhibition of hERG channels.
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Affiliation(s)
- Young Shin Joo
- Department of Pharmacology, College of Medicine, The Catholic University of Korea, Seoul 06591, Korea
| | - Hong Joon Lee
- Department of Physiology, College of Medicine, The Catholic University of Korea, Seoul 06591, Korea
| | - Jin-Sung Choi
- College of Pharmacy, Integrated Research Institute of Pharmaceutical, The Catholic University of Korea, Seoul 14662, Korea
| | - Ki-Wug Sung
- Department of Pharmacology, College of Medicine, The Catholic University of Korea, Seoul 06591, Korea
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Andrade EL, Bento AF, Cavalli J, Oliveira SK, Schwanke RC, Siqueira JM, Freitas CS, Marcon R, Calixto JB. Non-clinical studies in the process of new drug development - Part II: Good laboratory practice, metabolism, pharmacokinetics, safety and dose translation to clinical studies. Braz J Med Biol Res 2016; 49:e5646. [PMID: 27982281 PMCID: PMC5188860 DOI: 10.1590/1414-431x20165646] [Citation(s) in RCA: 76] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Accepted: 09/23/2016] [Indexed: 11/22/2022] Open
Abstract
The process of drug development involves non-clinical and clinical studies. Non-clinical studies are conducted using different protocols including animal studies, which mostly follow the Good Laboratory Practice (GLP) regulations. During the early pre-clinical development process, also known as Go/No-Go decision, a drug candidate needs to pass through several steps, such as determination of drug availability (studies on pharmacokinetics), absorption, distribution, metabolism and elimination (ADME) and preliminary studies that aim to investigate the candidate safety including genotoxicity, mutagenicity, safety pharmacology and general toxicology. These preliminary studies generally do not need to comply with GLP regulations. These studies aim at investigating the drug safety to obtain the first information about its tolerability in different systems that are relevant for further decisions. There are, however, other studies that should be performed according to GLP standards and are mandatory for the safe exposure to humans, such as repeated dose toxicity, genotoxicity and safety pharmacology. These studies must be conducted before the Investigational New Drug (IND) application. The package of non-clinical studies should cover all information needed for the safe transposition of drugs from animals to humans, generally based on the non-observed adverse effect level (NOAEL) obtained from general toxicity studies. After IND approval, other GLP experiments for the evaluation of chronic toxicity, reproductive and developmental toxicity, carcinogenicity and genotoxicity, are carried out during the clinical phase of development. However, the necessity of performing such studies depends on the new drug clinical application purpose.
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Affiliation(s)
- E L Andrade
- Centro de Inovação e Ensaios Pré-clínicos, Florianópolis, SC, Brasil
| | - A F Bento
- Centro de Inovação e Ensaios Pré-clínicos, Florianópolis, SC, Brasil
| | - J Cavalli
- Centro de Inovação e Ensaios Pré-clínicos, Florianópolis, SC, Brasil
| | - S K Oliveira
- Centro de Inovação e Ensaios Pré-clínicos, Florianópolis, SC, Brasil
| | - R C Schwanke
- Centro de Inovação e Ensaios Pré-clínicos, Florianópolis, SC, Brasil
| | - J M Siqueira
- Centro de Inovação e Ensaios Pré-clínicos, Florianópolis, SC, Brasil
| | - C S Freitas
- Centro de Inovação e Ensaios Pré-clínicos, Florianópolis, SC, Brasil
| | - R Marcon
- Centro de Inovação e Ensaios Pré-clínicos, Florianópolis, SC, Brasil
| | - J B Calixto
- Centro de Inovação e Ensaios Pré-clínicos, Florianópolis, SC, Brasil
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Henck JW, Elayan I, Vorhees C, Fisher JE, Morford LL. Current Topics in Postnatal Behavioral Testing. Int J Toxicol 2016; 35:499-520. [DOI: 10.1177/1091581816657082] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The study of developmental neurotoxicity (DNT) continues to be an important component of safety evaluation of candidate therapeutic agents and of industrial and environmental chemicals. Developmental neurotoxicity is considered to be an adverse change in the central and/or peripheral nervous system during development of an organism and has been primarily evaluated by studying functional outcomes, such as changes in behavior, neuropathology, neurochemistry, and/or neurophysiology. Neurobehavioral evaluations are a component of a wide range of toxicology studies in laboratory animal models, whereas neurochemistry and neurophysiology are less commonly employed. Although the primary focus of this article is on neurobehavioral evaluation in pre- and postnatal development and juvenile toxicology studies used in pharmaceutical development, concepts may also apply to adult nonclinical safety studies and Environmental Protection Agency/chemical assessments. This article summarizes the proceedings of a symposium held during the 2015 American College of Toxicology annual meeting and includes a discussion of the current status of DNT testing as well as potential issues and recommendations. Topics include the regulatory context for DNT testing; study design and interpretation; behavioral test selection, including a comparison of core learning and memory systems; age of testing; repeated testing of the same animals; use of alternative animal models; impact of findings; and extrapolation of animal results to humans. Integration of the regulatory experience and scientific concepts presented during this symposium, as well as from subsequent discussion and input, provides a synopsis of the current state of DNT testing in safety assessment, as well as a potential roadmap for future advancement.
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Affiliation(s)
| | - Ikram Elayan
- US Food and Drug Administration, Silver Spring, MD, USA
| | - Charles Vorhees
- Cincinnati Children’s Research Foundation, Cincinnati, OH, USA
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Accardi MV, Troncy E, Abtout S, Ascah A, Maghezzi S, Authier S. Rat cardiovascular telemetry: Marginal distribution applied to positive control drugs. J Pharmacol Toxicol Methods 2016; 81:120-7. [PMID: 27039258 DOI: 10.1016/j.vascn.2016.03.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Revised: 03/25/2016] [Accepted: 03/27/2016] [Indexed: 11/26/2022]
Abstract
Cardiovascular effects are considered frequent during drug safety testing. This investigation aimed to characterize the pharmacological response of the conscious telemetered rat in vivo model to known cardiovascular active agents. These effects were analyzed using statistical analysis and cloud representation with marginal distribution curves for the contractility index and heart rate as to assess the effect relationship between cardiac variables. Arterial blood pressure, left ventricular pressure, electrocardiogram and body temperature were monitored. The application of data cloud with marginal distribution curves to heart rate and contractility index provided an interesting tactic during the interpretation of drug-induced changes particularly during selective time resolution (i.e. marginal distribution curves restricted to Tmax). Taken together, the present data suggests that marginal distribution curves can be a valuable interpretation strategy when using the rat cardiovascular telemetry model to detect drug-induced cardiovascular effects. Marginal distribution curves could also be considered during the interpretation of other inter-dependent parameters in safety pharmacology studies.
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Affiliation(s)
- M V Accardi
- CiToxLAB North America, 445 Armand Frappier, Laval, QC H7V 4B3, Canada
| | - E Troncy
- Faculty of Veterinary Medicine, University of Montreal, P.O. box 5000, St-Hyacinthe, QC J2S 7C6, Canada
| | - S Abtout
- CiToxLAB North America, 445 Armand Frappier, Laval, QC H7V 4B3, Canada
| | - A Ascah
- CiToxLAB North America, 445 Armand Frappier, Laval, QC H7V 4B3, Canada
| | - S Maghezzi
- CiToxLAB North America, 445 Armand Frappier, Laval, QC H7V 4B3, Canada
| | - S Authier
- CiToxLAB North America, 445 Armand Frappier, Laval, QC H7V 4B3, Canada; Faculty of Veterinary Medicine, University of Montreal, P.O. box 5000, St-Hyacinthe, QC J2S 7C6, Canada.
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8
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Phillips TJ, Shabani S. An animal model of differential genetic risk for methamphetamine intake. Front Neurosci 2015; 9:327. [PMID: 26441502 PMCID: PMC4585292 DOI: 10.3389/fnins.2015.00327] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Accepted: 08/31/2015] [Indexed: 11/13/2022] Open
Abstract
The question of whether genetic factors contribute to risk for methamphetamine (MA) use and dependence has not been intensively investigated. Compared to human populations, genetic animal models offer the advantages of control over genetic family history and drug exposure. Using selective breeding, we created lines of mice that differ in genetic risk for voluntary MA intake and identified the chromosomal addresses of contributory genes. A quantitative trait locus was identified on chromosome 10 that accounts for more than 50% of the genetic variance in MA intake in the selected mouse lines. In addition, behavioral and physiological screening identified differences corresponding with risk for MA intake that have generated hypotheses that are testable in humans. Heightened sensitivity to aversive and certain physiological effects of MA, such as MA-induced reduction in body temperature, are hallmarks of mice bred for low MA intake. Furthermore, unlike MA-avoiding mice, MA-preferring mice are sensitive to rewarding and reinforcing MA effects, and to MA-induced increases in brain extracellular dopamine levels. Gene expression analyses implicate the importance of a network enriched in transcription factor genes, some of which regulate the mu opioid receptor gene, Oprm1, in risk for MA use. Neuroimmune factors appear to play a role in differential response to MA between the mice bred for high and low intake. In addition, chromosome 10 candidate gene studies provide strong support for a trace amine-associated receptor 1 gene, Taar1, polymorphism in risk for MA intake. MA is a trace amine-associated receptor 1 (TAAR1) agonist, and a non-functional Taar1 allele segregates with high MA consumption. Thus, reduced TAAR1 function has the potential to increase risk for MA use. Overall, existing findings support the MA drinking lines as a powerful model for identifying genetic factors involved in determining risk for harmful MA use. Future directions include the development of a binge model of MA intake, examining the effect of withdrawal from chronic MA on MA intake, and studying potential Taar1 gene × gene and gene × environment interactions. These and other studies are intended to improve our genetic model with regard to its translational value to human addiction.
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Affiliation(s)
- Tamara J Phillips
- VA Portland Health Care System Portland, OR, USA ; Department of Behavioral Neuroscience and Methamphetamine Abuse Research Center, Oregon Health & Science University Portland, OR, USA
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Antel J, Albayrak Ö, Heusch G, Banaschewski T, Hebebrand J. Assessment of potential cardiovascular risks of methylphenidate in comparison with sibutramine: do we need a SCOUT (trial)? Eur Arch Psychiatry Clin Neurosci 2015; 265:233-47. [PMID: 25149468 DOI: 10.1007/s00406-014-0522-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/18/2013] [Accepted: 08/01/2014] [Indexed: 12/20/2022]
Abstract
With the recent approval of methylphenidate (MPH) for treating attention-deficit/hyperactivity disorder (ADHD) in adults, the number of patients exposed will increase tremendously. The ongoing debate on the cardiovascular safety of MPH has triggered two large retrospective cohort studies in children and adolescents as well as in young to middle-aged adults. These studies looked into serious cardiovascular events (sudden cardiac death, acute myocardial infarction and stroke) as primary endpoints and concluded that MPH was safe after a mean duration of 2.1 years of follow-up in children and adolescents and mean duration of 0.33 years of current use in adults. The results are encouraging with respect to the short- and medium-term use of MPH. Without the inherent limitations of retrospective cohort studies, a prospective randomized, double-blind, placebo-controlled, multicenter trial in individuals stratified for cardiovascular risk factors would allow for an optimized risk assessment. With many millions of patients treated per year and drawing parallels to the lately discovered risks of sibutramine, another sympathomimetic with an overlapping mode of action and similar side effects on heart rate and blood pressure, we hypothesize that such a trial might be a dedicated risk mitigation strategy for public health. A critical assessment of cardiovascular side effects of MPH appears particularly warranted, because ADHD is associated with obesity, smoking and poor health in general. We summarize recent findings with the focus on cardiovascular risks of MPH in humans; we additionally analyze the limited number of rodent studies that have addressed cardiovascular risks of MPH.
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Affiliation(s)
- Jochen Antel
- Research-Unit of the Department of Child and Adolescent Psychiatry, Psychosomatics, and Psychotherapy, LVR-Klinikum Essen, University of Duisburg-Essen, IG1 Virchowstr. 171, 45147, Essen, Germany,
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Abstract
Whereas pharmacological responses tend to be fairly rapid in onset and are therefore detectable after a single dose, some diminish on repeated dosing, and others increase in magnitude and therefore can be missed or underestimated in single-dose safety pharmacology studies. Safety pharmacology measurements can be incorporated into repeat-dose toxicity studies, either routinely or on an ad hoc basis. Drivers for this are both scientific (see above) and regulatory (e.g. ICH S6, S7, S9). There are inherent challenges in achieving this: the availability of suitable technical and scientific expertise in the test facility, unsuitable laboratory conditions, use of simultaneous (as opposed to staggered) dosing, requirement for toxicokinetic sampling, unsuitability of certain techniques (e.g. use of anaesthesia, surgical implantation, food restriction), equipment availability at close proximity and sensitivity of the methods to detect small, clinically relevant, changes. Nonetheless, 'fit-for-purpose' data can still be acquired without requiring additional animals. Examples include assessment of behaviour, sensorimotor, visual and autonomic functions, ambulatory ECG and blood pressure, echocardiography, respiratory, gastrointestinal, renal and hepatic function. This is entirely achievable if the safety pharmacology measurements are relatively unobtrusive, both with respect to the animals and to the toxicology study itself. Careful pharmacological validation of any methods used, and establishing their detection sensitivity, is vital to ensure the credibility of generated data.
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Affiliation(s)
- Will S Redfern
- Drug Safety and Metabolism, AstraZeneca R&D, Darwin Building, 310 Cambridge Science Park, Cambridge, CB4 0WG, UK,
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Sümegi Z, Gácsi M, Topál J. Conditioned placebo effect in dogs decreases separation related behaviours. Appl Anim Behav Sci 2014. [DOI: 10.1016/j.applanim.2014.07.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Safety pharmacology — Current and emerging concepts. Toxicol Appl Pharmacol 2013; 273:229-41. [DOI: 10.1016/j.taap.2013.04.039] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2013] [Revised: 03/31/2013] [Accepted: 04/15/2013] [Indexed: 11/18/2022]
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Redfern WS, Ewart LC, Lainée P, Pinches M, Robinson S, Valentin JP. Functional assessments in repeat-dose toxicity studies: the art of the possible. Toxicol Res (Camb) 2013. [DOI: 10.1039/c3tx20093k] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
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Ward G, Milliken P, Patel B, McMahon N. Comparison of non-invasive and implanted telemetric measurement of blood pressure and electrocardiogram in conscious beagle dogs. J Pharmacol Toxicol Methods 2012; 66:106-13. [DOI: 10.1016/j.vascn.2012.04.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2012] [Revised: 03/26/2012] [Accepted: 04/06/2012] [Indexed: 10/28/2022]
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Moscardo E, McPhie G, Fasdelli N, Dorigatti R, Meecham K. An integrated cardiovascular and neurobehavioural functional assessment in the conscious telemetered cynomolgus monkey. J Pharmacol Toxicol Methods 2010; 62:95-106. [DOI: 10.1016/j.vascn.2010.06.006] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2010] [Accepted: 06/13/2010] [Indexed: 10/19/2022]
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Adeyemi O, Roberts S, Harris J, West H, Shome S, Dewhurst M. QA interval as an indirect measure of cardiac contractility in the conscious telemeterised rat: Model optimisation and evaluation. J Pharmacol Toxicol Methods 2009; 60:159-66. [DOI: 10.1016/j.vascn.2009.03.006] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2009] [Accepted: 03/10/2009] [Indexed: 11/28/2022]
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Moscardo E, Fasdelli N, Giarola A, Tontodonati M, Dorigatti R. An optimised neurobehavioural observation battery integrated with the assessment of cardiovascular function in the beagle dog. J Pharmacol Toxicol Methods 2009; 60:198-209. [DOI: 10.1016/j.vascn.2009.05.005] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2009] [Accepted: 05/13/2009] [Indexed: 11/25/2022]
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Norton K, Iacono G, Vezina M. Assessment of the pharmacological effects of inotropic drugs on left ventricular pressure and contractility: an evaluation of the QA interval as an indirect indicator of cardiac inotropism. J Pharmacol Toxicol Methods 2009; 60:193-7. [PMID: 19523528 DOI: 10.1016/j.vascn.2009.05.008] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2009] [Accepted: 05/28/2009] [Indexed: 11/19/2022]
Abstract
INTRODUCTION The ICH S7A and S7B guidelines require that effects of test substances on the cardiovascular system be assessed with respect to blood pressure, heart rate and electrocardiogram intervals. Where adverse effects are identified additional supplemental studies, including ventricular contractility, should be conducted as deemed appropriate. However, there is an absence of definitive guidance regarding when to pursue supplementary studies, in part due to ill-defined criteria of what constitutes an adverse effect and to surgical/technical monitoring limitations of study designs. However with advances in technology it is now feasible to develop models for assessing LVP and contractility in conjunction with standard assessments. The objectives of this study were to 1) develop a model for chronic evaluation of LVP and contractility, 2) illustrate changes in LV contractility without concurrent proportional changes in heart rate and/or systemic blood pressure and 3) determine if the QA interval, the time between the Q on the ECG and the beginning of the upstroke on the arterial blood pressure, can be used as a indicator of altered LV contractility. METHODS Dogs (N=4) were implanted with a telemetry transmitter. LVP, contractility, ECG and BP were assessed prior to and up to 24 h following administration of Atenolol (10 mg/kg) and Pimobendan (0.45 mg/kg). RESULTS Atenolol caused an approximately 30% decrease in HR, followed by a sustained decrease in maximum left ventricular contractility (+dP/dt mmHg/s). No effects were noted on blood pressure. Pimobendan caused a 100% increase in contractility (+dP/dt mmHg/s) which remained elevated for approximately 4 h. No effects were noted on blood pressure. Heart rate was highly variable initial decreasing, followed by a highly variable increase until 4 h postdose. Following administration of both compounds changes in maximum left ventricular contractility correlated with reverse changes in QA interval duration. DISCUSSION This model demonstrates that evaluation of LV contractility complements measurements of heart rate and blood pressure as part of a more complete cardiovascular safety assessment strategy. Furthermore, we demonstrate an apparent correlation between dP/dt and QA interval and concluded that QA interval can be utilized as an indicator of a potential inotropic effect. However further confirmation should be assessed through additional in-vivo measurements of LVP and contractility.
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Affiliation(s)
- K Norton
- Charles River Laboratories Preclinical Services, Montreal, Quebec, Canada.
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Hemodynamic and Cardiac Neurotransmitter-releasing Effects in Conscious Dogs of Attention- and Wake-promoting Agents: A Comparison of d-Amphetamine, Atomoxetine, Modafinil, and a Novel Quinazolinone H3 Inverse Agonist. J Cardiovasc Pharmacol 2009; 53:52-9. [DOI: 10.1097/fjc.0b013e318195a470] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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A functional observational battery in non-human primates for regulatory-required neurobehavioral assessments. J Pharmacol Toxicol Methods 2008; 58:88-93. [DOI: 10.1016/j.vascn.2008.05.002] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2008] [Accepted: 05/19/2008] [Indexed: 11/21/2022]
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Pugsley MK, Authier S, Curtis MJ. Principles of safety pharmacology. Br J Pharmacol 2008; 154:1382-99. [PMID: 18604233 PMCID: PMC2492105 DOI: 10.1038/bjp.2008.280] [Citation(s) in RCA: 146] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2008] [Revised: 06/09/2008] [Accepted: 06/12/2008] [Indexed: 11/09/2022] Open
Abstract
Safety Pharmacology is a rapidly developing discipline that uses the basic principles of pharmacology in a regulatory-driven process to generate data to inform risk/benefit assessment. The aim of Safety Pharmacology is to characterize the pharmacodynamic/pharmacokinetic (PK/PD) relationship of a drug's adverse effects using continuously evolving methodology. Unlike toxicology, Safety Pharmacology includes within its remit a regulatory requirement to predict the risk of rare lethal events. This gives Safety Pharmacology its unique character. The key issues for Safety Pharmacology are detection of an adverse effect liability, projection of the data into safety margin calculation and finally clinical safety monitoring. This article sets out to explain the drivers for Safety Pharmacology so that the wider pharmacology community is better placed to understand the discipline. It concludes with a summary of principles that may help inform future resolution of unmet needs (especially establishing model validation for accurate risk assessment). Subsequent articles in this issue of the journal address specific aspects of Safety Pharmacology to explore the issues of model choice, the burden of proof and to highlight areas of intensive activity (such as testing for drug-induced rare event liability, and the challenge of testing the safety of so-called biologics (antibodies, gene therapy and so on.).
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Affiliation(s)
- M K Pugsley
- Department of Toxicology & Pathology, Global Preclinical Development, Johnson & Johnson Pharmaceutical Research & Development Raritan, NJ, USA
| | - S Authier
- LAB Research Inc., 445 Armand Frappier, Laval Quebec, Canada
| | - M J Curtis
- Cardiovascular Division St Thomas' Hospital, King's College London, London, UK
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van der Linde HJ, Van Deuren B, Teisman A, Towart R, Gallacher DJ. The effect of changes in core body temperature on the QT interval in beagle dogs: a previously ignored phenomenon, with a method for correction. Br J Pharmacol 2008; 154:1474-81. [PMID: 18574451 PMCID: PMC2451335 DOI: 10.1038/bjp.2008.265] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
Background and purpose: Body core temperature (Tc) changes affect the QT interval, but correction for this has not been systematically investigated. It may be important to correct QT intervals for drug-induced changes in Tc. Experimental approach: Anaesthetized beagle dogs were artificially cooled (34.2 °C) or warmed (42.1 °C). The relationship between corrected QT intervals (QTcV; QT interval corrected according to the Van de Water formula) and Tc was analysed. This relationship was also examined in conscious dogs where Tc was increased by exercise. Key results: When QTcV intervals were plotted against changes in Tc, linear correlations were observed in all individual dogs. The slopes did not significantly differ between cooling (−14.85±2.08) or heating (−13.12±3.46) protocols. We propose a correction formula to compensate for the influence of Tc changes and standardize the QTcV duration to 37.5 °C: QTcVcT (QTcV corrected for changes in core temperature)=QTcV–14 (37.5 – Tc). Furthermore, cooled dogs were re-warmed (from 34.2 to 40.0 °C) and marked QTcV shortening (−29%) was induced. After Tc correction, using the above formula, this decrease was abolished. In these re-warmed dogs, we observed significant increases in T-wave amplitude and in serum [K+] levels. No arrhythmias or increase in pro-arrhythmic biomarkers were observed. In exercising dogs, the above formula completely compensated QTcV for the temperature increase. Conclusions and implications: This study shows the importance of correcting QTcV intervals for changes in Tc, to avoid misleading interpretations of apparent QTcV interval changes. We recommend that all ICH S7A, conscious animal safety studies should routinely measure core body temperature and correct QTcV appropriately, if body temperature and heart rate changes are observed.
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Affiliation(s)
- H J van der Linde
- Division of Janssen Pharmaceutica NV, Center of Excellence for Cardiovascular Safety Research, Johnson & Johnson Pharmaceutical Research and Development, Beerse, Belgium.
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Pugsley MK, Curtis MJ. Safety pharmacology methods: Anticipating the transition from long QT (LQTS) to short QT syndromes (SQTS)? J Pharmacol Toxicol Methods 2007; 56:87-90. [PMID: 17651991 DOI: 10.1016/j.vascn.2007.05.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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