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Abaimov DA, Kazanskaya RB, Ageldinov RA, Nesterov MS, Timoshina YA, Platova AI, Aristova IJ, Vinogradskaia IS, Fedorova TN, Volnova AB, Gainetdinov RR, Lopachev AV. Evaluation of Ouabain's Tissue Distribution in C57/Black Mice Following Intraperitoneal Injection, Using Chromatography and Mass Spectrometry. Int J Mol Sci 2024; 25:4318. [PMID: 38673903 PMCID: PMC11050293 DOI: 10.3390/ijms25084318] [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: 02/28/2024] [Revised: 04/01/2024] [Accepted: 04/10/2024] [Indexed: 04/28/2024] Open
Abstract
Cardiotonic steroids (CTSs), such as digoxin, are used for heart failure treatment. However, digoxin permeates the brain-blood barrier (BBB), affecting central nervous system (CNS) functions. Finding a CTS that does not pass through the BBB would increase CTSs' applicability in the clinic and decrease the risk of side effects on the CNS. This study aimed to investigate the tissue distribution of the CTS ouabain following intraperitoneal injection and whether ouabain passes through the BBB. After intraperitoneal injection (1.25 mg/kg), ouabain concentrations were measured at 5 min, 15 min, 30 min, 1 h, 3 h, 6 h, and 24 h using HPLC-MS in brain, heart, liver, and kidney tissues and blood plasma in C57/black mice. Ouabain was undetectable in the brain tissue. Plasma: Cmax = 882.88 ± 21.82 ng/g; Tmax = 0.08 ± 0.01 h; T1/2 = 0.15 ± 0.02 h; MRT = 0.26 ± 0.01. Cardiac tissue: Cmax = 145.24 ± 44.03 ng/g (undetectable at 60 min); Tmax = 0.08 ± 0.02 h; T1/2 = 0.23 ± 0.09 h; MRT = 0.38 ± 0.14 h. Kidney tissue: Cmax = 1072.3 ± 260.8 ng/g; Tmax = 0.35 ± 0.19 h; T1/2 = 1.32 ± 0.76 h; MRT = 1.41 ± 0.71 h. Liver tissue: Cmax = 2558.0 ± 382.4 ng/g; Tmax = 0.35 ± 0.13 h; T1/2 = 1.24 ± 0.7 h; MRT = 0.98 ± 0.33 h. Unlike digoxin, ouabain does not cross the BBB and is eliminated quicker from all the analyzed tissues, giving it a potential advantage over digoxin in systemic administration. However, the inability of ouabain to pass though the BBB necessitates intracerebral administration when used to investigate its effects on the CNS.
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Affiliation(s)
- Denis A. Abaimov
- Research Center of Neurology, Volokolamskoye Shosse 80, 125367 Moscow, Russia; (D.A.A.); (Y.A.T.); (T.N.F.)
| | - Rogneda B. Kazanskaya
- Research Center of Neurology, Volokolamskoye Shosse 80, 125367 Moscow, Russia; (D.A.A.); (Y.A.T.); (T.N.F.)
- Biological Department, Saint Petersburg State University, Universitetskaya Emb. 7/9, 199034 St. Petersburg, Russia; (I.J.A.); (A.B.V.)
| | - Ruslan A. Ageldinov
- Scientific Center for Biomedical Technologies of the Federal Biomedical Agency of Russia, 119435 Krasnogorsk, Russia; (R.A.A.); (M.S.N.)
| | - Maxim S. Nesterov
- Scientific Center for Biomedical Technologies of the Federal Biomedical Agency of Russia, 119435 Krasnogorsk, Russia; (R.A.A.); (M.S.N.)
| | - Yulia A. Timoshina
- Research Center of Neurology, Volokolamskoye Shosse 80, 125367 Moscow, Russia; (D.A.A.); (Y.A.T.); (T.N.F.)
- Biological Department, Lomonosov Moscow State University, Leninskiye Gory 1, 119991 Moscow, Russia
| | - Angelina I. Platova
- The Mental Health Research Center, Kashirskoye Shosse 34, 115522 Moscow, Russia;
| | - Irina J. Aristova
- Biological Department, Saint Petersburg State University, Universitetskaya Emb. 7/9, 199034 St. Petersburg, Russia; (I.J.A.); (A.B.V.)
- Institute of Translational Biomedicine, Saint Petersburg State University, Universitetskaya Emb. 7/9, 199034 St. Petersburg, Russia;
| | - Irina S. Vinogradskaia
- Non-State Private Educational Institution of Higher Professional Education, Moscow University for Industry and Finance “Synergy”, Meshchanskaya Street, 9/14, Building 1, 129090 Moscow, Russia;
| | - Tatiana N. Fedorova
- Research Center of Neurology, Volokolamskoye Shosse 80, 125367 Moscow, Russia; (D.A.A.); (Y.A.T.); (T.N.F.)
| | - Anna B. Volnova
- Biological Department, Saint Petersburg State University, Universitetskaya Emb. 7/9, 199034 St. Petersburg, Russia; (I.J.A.); (A.B.V.)
- Institute of Translational Biomedicine, Saint Petersburg State University, Universitetskaya Emb. 7/9, 199034 St. Petersburg, Russia;
| | - Raul R. Gainetdinov
- Institute of Translational Biomedicine, Saint Petersburg State University, Universitetskaya Emb. 7/9, 199034 St. Petersburg, Russia;
- Saint-Petersburg University Hospital, 199034 St. Petersburg, Russia
| | - Alexander V. Lopachev
- Research Center of Neurology, Volokolamskoye Shosse 80, 125367 Moscow, Russia; (D.A.A.); (Y.A.T.); (T.N.F.)
- Institute of Translational Biomedicine, Saint Petersburg State University, Universitetskaya Emb. 7/9, 199034 St. Petersburg, Russia;
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Bracken LM, Chan BSH, Buckley NA. Physiologically based pharmacokinetic modelling of acute digoxin toxicity and the effect of digoxin-specific antibody fragments. Clin Toxicol (Phila) 2018; 57:117-124. [PMID: 30306803 DOI: 10.1080/15563650.2018.1503288] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
CONTEXT Recommended doses of digoxin-specific antibody fragments (digoxin-Fab) for treatment of acute digoxin poisoning are pharmacokinetically unsubstantiated and theoretically excessive. Physiologically based pharmacokinetic (PBPK) modelling creates clinical simulations which are closely related to physiological and pharmacokinetic behaviour. This paper details the formulation of a PBPK model of digoxin and explores its use as a simulation tool for acute digoxin toxicity and its management. MATERIALS AND METHODS A PBPK model of digoxin was constructed and validated for acute digoxin poisoning management by comparing simulations with observed individual acute overdose patients. These simulations were compared with standard two-compartment PK model simulations. RESULTS PBPK model simulations showed good agreement with post-absorption plasma concentrations of digoxin measured in 6 acute overdose patients. PBPK predictions were accurate to 1.5-fold or less of observed clinical values, proving to be more accurate than two-compartment simulations of the same patients which produced up to a 4.9-fold change. CONCLUSIONS Compared to conventional two-compartment modelling, PBPK modelling is superior in generating realistic simulations of acute digoxin toxicity and the response to digoxin-Fab. Simulation capacity provides realistic, continuous data which has the potential to substantiate alternative, less expensive, and safer digoxin-Fab dosing strategies for the treatment of acute digoxin toxicity.
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Affiliation(s)
- Lucy M Bracken
- a Pharmacology, Sydney Medical School, University of Sydney , Sydney , Australia.,b Department of Emergency Medicine , Clinical Toxicology Unit, Prince of Wales Hospital , New South Wales , Australia
| | - Betty S H Chan
- b Department of Emergency Medicine , Clinical Toxicology Unit, Prince of Wales Hospital , New South Wales , Australia.,c New South Wales Poisons Information Centre , New South Wales , Australia
| | - Nicholas A Buckley
- a Pharmacology, Sydney Medical School, University of Sydney , Sydney , Australia.,c New South Wales Poisons Information Centre , New South Wales , Australia
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Tylutki Z, Polak S. Plasma vs heart tissue concentration in humans - literature data analysis of drugs distribution. Biopharm Drug Dispos 2015; 36:337-351. [PMID: 25765563 DOI: 10.1002/bdd.1944] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2014] [Revised: 01/05/2015] [Accepted: 03/04/2015] [Indexed: 12/12/2022]
Abstract
Little is known about the uptake of drugs into the human heart, although it is of great importance nowadays, when science desires to predict tissue level behavior rather than to measure it. Although the drug concentration in cardiac tissue seems a better predictor for physiological and electrophysiological changes than its level in plasma, knowledge of this value is very limited. Tissue to plasma partition coefficients (Kp) come to rescue since they characterize the distribution of a drug among tissues as being one of the input parameters in physiologically based pharmacokinetic (PBPK) models. The article reviews cardiac surgery and forensic medical studies to provide a reference for drug concentrations in human cardiac tissue. Firstly, the focus is on whether a drug penetrates into heart tissue at a therapeutic level; the provided values refer to antibiotics, antifungals and anticancer drugs. Drugs that directly affect cardiomyocyte electrophysiology are another group of interest. Measured levels of amiodarone, digoxin, perhexiline and verapamil in different sites in human cardiac tissue where the compounds might meet ion channels, gives an insight into how these more lipophilic drugs penetrate the heart. Much data are derived from postmortem studies and they provide insight to the cardiac distribution of more than 200 drugs. The analysis depicts potential problems in defining the active concentration location, what may indirectly suggest multiple mechanisms involved in the drug distribution within the heart. Copyright © 2015 John Wiley & Sons, Ltd.
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Affiliation(s)
- Zofia Tylutki
- Unit of Pharmacoepidemiology and Pharmacoeconomics, Department of Social Pharmacy, Faculty of Pharmacy, Jagiellonian University Medical College, Medyczna 9 Str, , 30-688, Cracow, Poland
| | - Sebastian Polak
- Unit of Pharmacoepidemiology and Pharmacoeconomics, Department of Social Pharmacy, Faculty of Pharmacy, Jagiellonian University Medical College, Medyczna 9 Str, , 30-688, Cracow, Poland
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Unintentional lethal overdose with metildigoxin in a 36-week-old infant--post mortem tissue distribution of metildigoxin and its metabolites by liquid chromatography tandem mass spectrometry. Forensic Sci Int 2014; 241:e23-7. [PMID: 24889325 DOI: 10.1016/j.forsciint.2014.05.013] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2014] [Revised: 05/12/2014] [Accepted: 05/15/2014] [Indexed: 11/20/2022]
Abstract
A massive lethal overdose with beta-metildigoxin in a 36-week-old infant is presented. Determination of beta-metildigoxin and its metabolites digoxin, digoxigenin and digoxigenin-monodigitoxosid is achieved by a liquid chromatographic mass spectrometric (LC-MS/MS) method. Measured concentrations for beta-metildigoxin and digoxin in peripheral blood were 40.2 ng/ml and 25.6 ng/ml, respectively. Tissue distribution showed highest concentrations in kidney tissue and gastric content. The metabolite digoxigenin-monodigitoxosid could be detected in heart blood, duodenal content, gastric content and fat tissue while the metabolite digoxigenin could only be detected in gastric content since the drug was given by a stomach tube.
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Neuhoff S, Yeo KR, Barter Z, Jamei M, Turner DB, Rostami-Hodjegan A. Application of permeability-limited physiologically-based pharmacokinetic models: part I-digoxin pharmacokinetics incorporating P-glycoprotein-mediated efflux. J Pharm Sci 2013; 102:3145-60. [PMID: 23703021 DOI: 10.1002/jps.23594] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2013] [Revised: 04/16/2013] [Accepted: 04/17/2013] [Indexed: 01/22/2023]
Abstract
A prerequisite for the prediction of the magnitude of P-glycoprotein (P-gp)-mediated drug-drug interactions between digoxin and P-gp inhibitors (e.g. verapamil and its metabolite norverapamil) or P-gp inducers (e.g. rifampicin) is a predictive pharmacokinetic model for digoxin itself. Thus, relevant in vitro metabolic, transporter and inhibitory data incorporated into permeability-limited models, such as the "advanced dissolution, absorption and metabolism" (ADAM) module and the permeability-limited liver (PerL) module, integrated with a mechanistic physiologically-based pharmacokinetic (PBPK) model such as that of the Simcyp Simulator (version 12.2) are necessary. Simulated concentration-time profiles of digoxin generated using the developed model were consistent with observed data across 31 independent studies [13 intravenous single dose (SD), 12 per oral SD and six multiple dose studies]. The fact that predicted tmax (time of maximum plasma concentration observed) and Cmax (maximum plasma concentration observed) of oral digoxin were similar to observed values indicated that the relative contributions of permeation and P-gp-mediated efflux in the model were appropriate. There was no indication of departure from dose proportionality over the dose range studied (0.25-1.5 mg). All dose normalised area under the plasma concentration-time curve profiles (AUCs) for the 0.25, 0.5, 0.75 and 1 mg doses resembled each other. Thus, PBPK modelling in conjunction with mechanistic absorption and distribution models and reliable in vitro transporter data can be used to assess the impact of dose on P-gp-mediated efflux (or otherwise).
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Affiliation(s)
- Sibylle Neuhoff
- Simcyp Limited (a Certara company), Blades Enterprise Centre, John Street, Sheffield S2 4SU, UK.
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Allonen H, Kanto J, Iisalo E. The foeto-maternal distribution of digoxin in early human pregnancy. ACTA PHARMACOLOGICA ET TOXICOLOGICA 2009; 39:477-80. [PMID: 989692 DOI: 10.1111/j.1600-0773.1976.tb03198.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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Abstract
Idiopathic intracranial hypertension is a disease with a predilection for young obese women. The most common symptoms are headache, transient visual obscuration and pulsatile tinnitus. The only focal neurologic finding is false-localizing 6th cranial nerve palsy. Papilledema is usually present and this can lead to optic atrophy with progressive permanent visual loss. The earliest visual loss is constriction of peripheral visual field, usually starting with the inferior nasal quadrant. Numerous theories have been entertained as to the pathogenesis but this still remains an open controversy. The most prevalent current theories involve increased resistance to cerebrospinal fluid reabsorption at the arachnoid granulations, either from intrinsic disease in the granulations or secondary to elevated pressure in the dural venous sinuses into which the cerebrospinal fluid is absorbed across the granulations. The syndrome of idiopathic intracranial hypertension was long ago recognized as a complication of recurrent otitis media with resultant thrombosis of the transverse and sigmoid dural venous sinuses. Cases secondary to dural venous sinus thrombosis are seldom encountered today because the incidence of chronic otitis is much less than in the past. The prevalent concept has been that the idiopathic cases in obese young women were not associated with pathology in the dural venous sinuses. A recent study using ATECO MR venography, which the authors claim to be more reliable than even conventional catheter venography, has demonstrated stenosis of the transverse and sigmoid dural venous sinuses distinguishes cases of idiopathic intracranial hypertension from controls with a high degree of sensitivity and specificity. The authors believe the stenosis is secondary to intracranial hypertension but that it may further aggravate the hypertension when it occurs.
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Affiliation(s)
- James Goodwin
- University of Illinois, Eye & Ear Infirmary, Chicago, IL 60612, USA.
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Ritz S, Harding P, Martz W, Schütz HW, Kaatsch HJ. Measurement of digitalis-glycoside levels in ocular tissues: a way to improve postmortem diagnosis of lethal digitalis-glycoside poisoning? I. Digoxin. Int J Legal Med 1992; 105:149-54. [PMID: 1419875 DOI: 10.1007/bf01625167] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Prompted by animal studies reporting the accumulation of digitalis-glycosides in ocular tissues, we investigated whether measurement of digoxin levels in human ocular tissues can improve the postmortem diagnosis of lethal digoxin intoxication. Digoxin was measured in the vitreous humor and choroid-retina of patients who had received in-patient treatment with digoxin prior to death (therapeutic group) and in a single case of suicidal intoxication. The results were compared with the digoxin levels in the femoral vein blood, myocardium, kidney and liver, and evaluated in light of the medical history of each patient. In the therapeutic group the mean digoxin level was higher in the choroid-retina than in other tissues and body fluids. The range of variation in levels in the choroid-retina following therapeutic doses was comparable to that in the other tissues. An extremely high level of digoxin was present in the choroid-retina in the case of suicidal intoxication. In all cases, levels in the vitreous humor were very low compared to those in the choroid-retina. Hence, it is unlikely that significant distortion of choroid-retinal levels occurs due to postmortem diffusion of digoxin into the vitreous body. Our results indicate that measurement of digoxin levels in the choroid-retina can aid the postmortem diagnosis of lethal digoxin intoxication.
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Affiliation(s)
- S Ritz
- Institut für Rechtsmedizin, Christian-Albrechts-Universität zu Kiel, Federal Republic of Germany
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9
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Abstract
Digoxin toxicity remains a common medical problem for both adults and children. In addition to a vastly improved understanding of the mechanisms for digoxin action on the heart, there are now data which clearly demonstrate that there are potentially important developmental differences in both the pharmacodynamics and pharmacokinetics of digoxin which have a direct impact on its efficacy and toxicity profile. The developmental pharmacokinetics of the drug have been extensively studied such that profiles for age-dependent differences in the apparent volume of distribution, plasma and renal clearance and elimination half-life now exist. It is these data which have also produced the current age-specific dosing guidelines for the therapeutic administration of digoxin in various paediatric subpopulations. Despite this new knowledge, both accidental and iatrogenic digoxin toxicity still occurs in paediatric patients, with potentially life-threatening arrhythmias being produced when steady-state serum digoxin concentrations exceed 5.1 nmol/L. Consequently, the clinician may be faced with the decision to use antidotal therapy with digoxin-specific Fab fragments (d-Fab). This article reviews the developmental basis for digoxin disposition and its pharmacological and toxic effects. Additionally, the treatment of acute digoxin toxicity in children is reviewed, especially as pertains to the therapeutic use of d-Fab.
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Affiliation(s)
- T G Wells
- Department of Pediatrics, University of Arkansas for Medical Sciences, Little Rock
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10
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Ottosson A, Edvinsson L, Sjögren A, Löwenhielm P. Digoxin, magnesium, and potassium levels in a forensic autopsy material of sudden death from ischemic heart disease. ZEITSCHRIFT FUR RECHTSMEDIZIN. JOURNAL OF LEGAL MEDICINE 1988; 101:27-36. [PMID: 3218385 DOI: 10.1007/bf00205321] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
In 91 cases where the cause of death was heart disease, digoxin, Mg and K concentrations in serum and ventricular myocardium were measured post mortem. Forty per cent were positive for digoxin in both serum and myocardium. The mean serum level was 5.1 +/- 2.4 nmol/l and the mean myocardial level was 42.6 +/- 27.5 ng/g. Correlation could be established between serum and myocardial concentrations of digoxin. There were statistically significant differences in serum as well as in myocardial digoxin levels in persons on 0.13 mg and 0.25 mg per day, respectively. Myocardial levels of Mg and K were low as generally found in persons with ischemic heart disease. There was no correlation between these levels and myocardial digoxin concentrations. Caution must be exercised in the assessment of digoxin results from cadaver samples because of the postmortem rise of digoxin serum concentrations. Considering this fact, the results still indicate that the prevalence of toxic digoxin concentrations might be more common than previously thought.
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Affiliation(s)
- A Ottosson
- Department of Forensic Medicine, University of Lund, Sweden
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12
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Minimizing Analytical Interferences from Digoxin-Like Immunoreactive Substances (DLIS) in Cases of Digoxin Toxicity. J Forensic Sci 1987. [DOI: 10.1520/jfs12369j] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Digoxin-Like Immunoreactive Substance in Postmortem Blood of Infants and Children. J Forensic Sci 1985. [DOI: 10.1520/jfs10967j] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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15
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Abstract
There is a narrow difference between the therapeutic and toxic ranges of cardiac glycosides. The availability in the past decade of radioimmunoassays for accurate measurement of these glycosides has resulted in an improved understanding of their pharmacokinetics and clinical use. Despite these advances, however, digitalis toxicity is still a common problem in infants and children.
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Tissue Concentrations at Autopsy in Infants and Children Receiving Therapeutic Digoxin. J Forensic Sci 1984. [DOI: 10.1520/jfs11644j] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Abstract
The concentration of digoxin in tissues and the content of the drug in various organs are reported in 36 infants and children. Sixteen received the drug on a short-term basis and 20 on a long-term basis. The drug was given intravenously to 12, orally to 17, and by intramuscular injection to 7. The study was conducted to determine distribution of digoxin in infants and children and to examine the forensic implications related to digoxin overdosage. Upper therapeutic concentration thresholds for digoxin were established in various tissues. These are different for preterm and full-term neonates than for older children and adults; for example, adult and neonatal values for postmortem blood specimens are 8 and 15 ng/ml, and for ventricular myocardium are 250 and 450 ng/g, respectively. The chronically digitalized premature infant retains in most tissues a considerably larger fraction of digoxin than more mature infants and children. This is in accord with previously demonstrated lower renal digoxin levels in premature infants attributed to their reduced ability to excrete this drug.
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Kelly JG, McMillen RM, McDevitt DG. The effect of digoxin on 86rubidium uptake by erythrocytes from mothers and babies. Br J Clin Pharmacol 1983; 15:49-53. [PMID: 6849744 PMCID: PMC1427824 DOI: 10.1111/j.1365-2125.1983.tb01462.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
1 The uptake of 86rubidium by erythrocytes from mothers and babies has been used as a model system to investigate possible differences in sensitivity to digoxin in the very young. 2 While total 86rubidium uptake was not significantly different between mothers and babies, the digoxin-sensitive proportion was higher in neonatal erythrocytes. Neonatal cells were less sensitive to digoxin, demonstrated by the requirement for a larger amount of digoxin to inhibit 86rubidium uptake and this was accompanied by an increase in numbers of specific erythrocyte binding sites for digoxin. 3 These results provide further evidence in support of the hypothesis of decreased sensitivity to digoxin in the very young.
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Marzo A, Ghirardi P, Preti A, Lombardo A, Azzini M, Marini A. Subcellular distribution of deslanatoside C in myocardium of newborn, growing and adult rabbit. PHARMACOLOGICAL RESEARCH COMMUNICATIONS 1982; 14:31-9. [PMID: 7071099 DOI: 10.1016/s0031-6989(82)80049-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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Sheiner LB, Benet LZ, Pagliaro LA. A standard approach to compiling clinical pharmacokinetic data. JOURNAL OF PHARMACOKINETICS AND BIOPHARMACEUTICS 1981; 9:59-127. [PMID: 7014827 DOI: 10.1007/bf01059343] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
A standard format for a Clinical Pharmacokinetic Summary is proposed. It consists of a heading, tables, notes, and references for each drug reviewed. The table presents a unified and logical set of clinically useful population pharmacokinetic parameters. They concern four major areas: absorption, distribution, elimination, and the relationship of concentration to effect. Within each major group, parameters dealing with extents and rates of processes are given. Each such parameter is really two: a population mea value (for example, average volume of distribution) and the standard deviation of individual values about this mean. The first value allows individual predictions of dosage or drug level to be made; the second allows computation of the likely proximity of subsequently observed quantities to those predictions. The table presents single consensus values for each population parameter, rather than a list of values. A procedure for computing these consensus values, and for revising them in the light of new data, or reinterpreted old data, is given. Examples of Summaries are given. The method appears applicable to a variety of drugs. We suggest our approach as a standard one for preparing Clinical Pharmacokinetic Summaries, and urge our colleagues to consider it for that purpose.
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Lang D, Hofstetter R, von Bernuth G. Postmortem tissue and plasma concentrations of digoxin in newborns and infants. Eur J Pediatr 1978; 128:151-61. [PMID: 668723 DOI: 10.1007/bf00444300] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Postmortem tissue and plasma concentrations of digoxin were studied in 13 premature newborns, 6 mature newborns, and 5 older infants (age 1 to 14 months). The pertinent results of our study are as follows: The tissue digoxin concentrations tend to be higher in premature and mature newborns than in infants. This difference is statisitcally significant with respect to the concentration in myocardium and skeletal muscle. The renal digoxin concentration of premature newborns is significantly lower than that of mature newborns, the tissue concentrations in the other organs examined being essentially equal. In all age groups examined, skeletal muscle contains the greatest portion of digoxin, followed by the liver. The relation of myocardial to plasma digoxin concentration shows no significant difference between the various age groups. Within the groups, the variation is relatively large.
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25
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Marzo A, Ghirardi P, Lorenzi G, Marini A. Tissues concentration and excretion of deslanatoside C-3H in newborn and growing rabbits. NAUNYN-SCHMIEDEBERG'S ARCHIVES OF PHARMACOLOGY 1978; 302:73-6. [PMID: 652056 DOI: 10.1007/bf00586600] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Deslanatoside C-3H was injected (i.p. 50 microgram/kg) into rabbits of 1, 4, 10, 20 days and more than 1 year old. The rabbits were sacrificed 2 and 6 h after dosing. Levels in all tissues were higher in newborn rabbits, decreased in the older animals and then in most tissues increased in adults to different degrees, showing the highest values in kidneys. Biliary excretion and above all urinary excretion increased with age. Levels in atria, ventricles, aorta and liver in rabbits 1 and 4 days old were consistently higher at the 6th h than those at the 2nd h, these tissues showing a particularly marked avidity with Deslanatoside C; in the older animals this behaviour was reversed. These data and those of other Authors working on other glycosides (incleding Digoxin) and other species (including newborn children) lead to the conclusion that digitalis glycosides in new born species are excreted at a lower rate and incorporated in the body tissues at a higher rate than in adults. They may also in part explain the large dosages employed in human infants in comparison with adults, as the higher distribtuion volume retains a large amount of the injected glycoside.
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Lang D, Hofstetter R, von Bernuth G. [Plasma digoxin concentration in different age groups (author's transl)]. KLINISCHE WOCHENSCHRIFT 1978; 56:93-5. [PMID: 628195 DOI: 10.1007/bf01480089] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Plasma digoxin concentration during maintenance therapy with digoxin was determined in premature and mature newborns, infants, children and adults. The plasma digoxin concentration of newborns was significantly higher than in adults; in addition, in the group of premature newborns it also was higher than in infants and children. These differences in plasma digoxin concentrations may be explained by differences in dose, volume of distribution and excretion rate of digoxin in the various age groups.
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Harrison LI, Gibaldi M. Physiologically based pharmacokinetic model for digoxin disposition in dogs and its preliminary application to humans. J Pharm Sci 1977; 66:1679-83. [PMID: 925929 DOI: 10.1002/jps.2600661206] [Citation(s) in RCA: 54] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
A physiologically based pharmacokinetic model for digoxin disposition developed in the rat was modified to account for the interspecies differences in tissue-to-plasma digoxin concentration ratios and applied to the dog. The model provided a quantitative assessment of the time course of digoxin concentrations in dog plasma, various tissues, and urine. It also predicted the effect of renal failure on digoxin pharmacokinetics in the dog. An attempt to scale the dog model to humans by simply considering differences in organ volumes, organ flow rates, and digoxin clearances was partially successful. Good predictions of plasma digoxin concentration and urinary digoxin excretion after a single dose and of steady-state plasma, heart, and skeletal muscle digoxin concentrations were obtained. However, the model predicted considerably higher kidney digoxin concentrations than are actually found. Although the model adequately characterized the time course of digoxin concentrations in patients with moderate renal impairment, it provided a relatively poor fit to that observed in anuric patients.
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Harrison LI, Gibaldi M. Physiologically based pharmacokinetic model for digoxin distribution and elimination in the rat. J Pharm Sci 1977; 66:1138-42. [PMID: 894501 DOI: 10.1002/jps.2600660822] [Citation(s) in RCA: 57] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
A plasma flow rate-limited pharmacokinetic model was developed to describe the distribution of digoxin to the heart, liver, kidneys, skeletal muscle, and GI tract in the rat. The model also provides for renal, hepatic (metabolic and biliary), and GI clearance as well as for biliary and GI secretion and GI reabsorption of digoxin. Predicted concentrations of digoxin in the heart, liver, skeletal muscle, and plasma were consistent with experimental observations in conscious rats after an intravenous dose. The model was extended to describe digoxin concentrations in the plasma of bile duct-ligated rats and ureter-ligated rats, simply by modifying appropriate clearance parameters. Excellent agreement was obtained between predicted and observed urinary excretion rates of digoxin for 12 hr after in intravenous dose to normal and bile duct-ligated rats.
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Abstract
The distribution and elimination of intravenous digoxin were investigated in seven neonates and infants with heart failure. Serum digoxin concentrations during a 24 h period were determined by radioimmunoassay, using 125I as tracer. The serum values declined biexponentially after the injection and could be fitted to a two-compartment open model by non-linear least-squares regression. The calculated mean half-lives of the distribution (alpha) phase in neonates and infants were 37 and 28 min, respectively. The mean half-life of the elimination (beta) phase in neonates was 44 h, as compared to 19 h in infants. The mean volume of the central compartment and the mean volume of distribution at steady-state were calculated to be 1.3 and 9.91/kg, respectively; no significant differences between neonates and infants were found. The relation between these volumes indicates that digoxin is extensively distributed in tissues. The steady-state distribution volumes of digoxin in neonates and infants exceed those reported in adults. The larger volume of distribution might explain in part why infants with cardiac insufficiency require larger doses of digoxin than adults (on a mg/kg body weight basis) to obtain the same serum concentrations. Elimination of digoxin from the body was slower in neonates than in infants.
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Abstract
The bioavailability of digoxin in solution was studied in 4 newbron infants with heart failure. Serum digoxin concentrations were determined by radioimmunoassay using 125I. Bioavailability was estimated by camparison of the areas under the 8-h serum concentration curves (8-h AUC) after intravenous and oral administration of the glycoside. After oral administration of digoxin (1/4 of the digitalizing dose, 0.05 mg/kg bw), peak serum values of 2.3-4.4 ng/ml were reached within 30-90 min. After intravenous administration of the same amount of the glycoside, there was a rapid decrease in serum concentration during the first 2 h, and after about 4 h the serum concentration curves paralled those obtained after oral dosing. Based on within subject comparison of intravenous and oral 8-h AUC'S, the mean bioavailability of digoxin was estimated to be 72 per cent (range 52-79 per cent). It was concluded that digoxin in solution, given to infants with mild to moderate heart failure, is well absorbed and biologically available to the same extent as in adults.
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