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Marsella R, White S, Fadok VA, Wilson D, Mueller R, Outerbridge C, Rosenkrantz W. Equine allergic skin diseases: Clinical consensus guidelines of the World Association for Veterinary Dermatology. Vet Dermatol 2023; 34:175-208. [PMID: 37154488 DOI: 10.1111/vde.13168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Revised: 02/03/2023] [Accepted: 02/26/2023] [Indexed: 05/10/2023]
Abstract
BACKGROUND Allergic skin diseases are common in horses worldwide. The most common causes are insect bites and environmental allergens. OBJECTIVES To review the current literature and provide consensus on pathogenesis, diagnosis, treatment and prevention. MATERIALS AND METHODS The authors reviewed the literature up to November 2022. Results were presented at North America Veterinary Dermatology Forum (2021) and European Veterinary Dermatology Congress (2021). The report was available to member organisations of the World Association for Veterinary Dermatology for feedback. CONCLUSIONS AND CLINICAL RELEVANCE Insect bite hypersensitivity (IBH) is the best characterised allergic skin disease. An immunoglobulin (Ig)E response against Culicoides salivary antigens is widely documented. Genetics and environmental factors play important roles. Tests with high sensitivity and specificity are lacking, and diagnosis of IBH is based on clinical signs, seasonality and response to insect control. Eosinophils, interleukin (IL)-5 and IL-31 are explored as therapeutic targets. Presently, the most effective treatment is insect avoidance. Existing evidence does not support allergen-specific immunotherapy (ASIT) using commercially available extracts of Culicoides. Hypersensitivity to environmental allergens (atopic dermatitis) is the next most common allergy. A role for IgE is supported by serological investigation, skin test studies and positive response to ASIT. Prospective, controlled, randomised studies are limited, and treatment relies largely on glucocorticoids, antihistamines and ASIT based on retrospective studies. Foods are known triggers for urticaria, yet their role in pruritic dermatitis is unknown. Recurrent urticaria is common in horses, yet our understanding is limited and focussed on IgE and T-helper 2 cell response. Prospective, controlled studies on treatments for urticaria are lacking. Glucocorticoids and antihistamines are primary reported treatments.
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Affiliation(s)
- R Marsella
- Department of Small Animal Clinical Sciences, College of Veterinary Medicine, University of Florida, Gainesville, Florida, USA
| | - S White
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, California, USA
| | - V A Fadok
- Zoetis, US PET CARE, Bellaire, Texas, USA
| | - D Wilson
- School of Clinical Veterinary Sciences, University of Bristol, Bristol, UK
| | - R Mueller
- Medizinische Keleintierklinik, Zentrum für klinische Tiermedizin, LMU, Munich, Germany
| | - C Outerbridge
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, California, USA
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2
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Adam E. Identifying bacterial infections in synovial structures—When will the Cavalry arrive? EQUINE VET EDUC 2021. [DOI: 10.1111/eve.13525] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- E. Adam
- Maxwell H Gluck Equine Research Center University of Kentucky Lexington Kentucky 40511 USA
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3
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Ekstrand C, Pettersson H, Gehring R, Hedeland M, Adolfsson S, Lilliehöök I. Prednisolone in Dogs-Plasma Exposure and White Blood Cell Response. Front Vet Sci 2021; 8:666219. [PMID: 34179161 PMCID: PMC8219870 DOI: 10.3389/fvets.2021.666219] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Accepted: 05/14/2021] [Indexed: 11/13/2022] Open
Abstract
Glucocorticoids such as prednisolone are commonly used in dogs but there is sparse quantitative pharmacokinetic and pharmacodynamic information of this drug in this species. The objective of this study was to quantitatively characterize the concentration-effect relationship for prednisolone in dogs on neutrophil and lymphocyte trafficking and cortisol suppression. Nine beagles, 2–12 years old and part of a group for teaching/research were used in a 4-way crossover experiment including two treatments, active or placebo, administered either per os (PO) or intravenously (IV). Plasma was analyzed for prednisolone and cortisol using ultra-high performance liquid chromatography – tandem mass spectrometry. Leucocyte counts were performed in whole blood. Data was then analyzed by non-linear mixed effect modeling to estimate pharmacokinetic and pharmacodynamic parameters. After administration of prednisolone sodium succinate IV, the typical value (between subject variation) for total body prednisolone clearance was 1,370 ml/h·kg (13.4%). The volumes of the central and peripheral compartment were 2,300 ml/kg (10.7%) and 600 ml/kg (16.0%), respectively. The terminal plasma half-life was 1.7 h. The prednisolone plasma concentration producing 50% of the maximum response was 10 ng/mL (90.3%), 22.5 ng/ml (52.3%) and 0.04 ng/mL (197.3%) for neutrophil, lymphocyte and cortisol response, respectively. The administered dose (1 mg/kg) increased neutrophil and decreased lymphocyte numbers but not over the entire dosage interval of 24 h, due to the short half-life. However, glucocorticoids have a wide range of responses. An anti-inflammatory response due to altered gene transcription might have a longer duration. Future studies on the anti-inflammatory potency together with data presented are needed to optimize future dosage recommendations in dogs.
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Affiliation(s)
- Carl Ekstrand
- Division of Pharmacology and Toxicology, Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Helena Pettersson
- Division of Clinical Pathology, Department of Clinical Sciences, Swedish University of Agricultural Sciences, Uppsala, Sweden.,Clinical Pathology Laboratory, University Animal Hospital, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Ronette Gehring
- Division of Pharmacology and Toxicology, Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, Uppsala, Sweden.,Division of Veterinary and Comparative Pharmacology, Department of Population Health Sciences, Utrecht University, Utrecht, Netherlands
| | - Mikael Hedeland
- Department of Chemistry, Environment and Feed Hygiene, National Veterinary Institute, Uppsala, Sweden.,Department of Medicinal Chemistry, Uppsala University, Uppsala, Sweden
| | - Sara Adolfsson
- Division of Pharmacology and Toxicology, Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Inger Lilliehöök
- Division of Clinical Pathology, Department of Clinical Sciences, Swedish University of Agricultural Sciences, Uppsala, Sweden.,Clinical Pathology Laboratory, University Animal Hospital, Swedish University of Agricultural Sciences, Uppsala, Sweden
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McClure S, Fenger C, Kersh K, Brown B, Maylin G, Duer W, Dirikolu L, Brewer K, Machin J, Tobin T. Dexamethasone serum concentrations after intravenous administration in horses during race training. COMPARATIVE EXERCISE PHYSIOLOGY 2021. [DOI: 10.3920/cep200015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Dexamethasone (DXM) sodium phosphate is a widely used corticosteroid for inflammatory conditions in horses, regulated in racing jurisdictions in the USA by a 0.005 ng/ml serum/plasma threshold. This study seeks to describe serum concentrations of DXM at 48 and 72 h after intravenous administration of 20 mg DXM sodium phosphate over 1 to 5 days, and to identify a possible source of DXM overages. 74 horses (39 Thoroughbreds, 13 Standardbreds, 22 Quarter Horses) in active race training received 20 mg DXM sodium phosphate. Serum was collected before injection, at 48 and 72 h post last injection, and analysed by LC/MS-MS (limit of quantification (LOQ) = 2.5 pg/ml). No differences were identified by ANOVA (P≤0.05) for racing breeds, age, gender or the number of days of DXM sodium phosphate administration, so data were pooled for each time point. The DXM serum concentration at 48 h (mean ± standard deviation, range) was 2.18±1.56 pg/ml (<2.5 to 40 pg/ml). Summary statistics could not be derived for 72 h DXM serum concentration data owing to censored data, but ranged from <2.5 to 95.8 pg/ml. There was one extreme outlier (Tukey) at 48 h, and two extreme outliers at 72 h. A separate study was conducted using sedentary experimental horses to determine the likelihood that positive DXM samples could result from environmental transfer. Urine was collected from a mare 2 to 3 h post administration of 20 mg DXM. Hay with 100 ml of the DXM (17 ng/ml) containing urine was offered to each of six experimental horses and blood was collected at 0, 4, 8, 12, 16, 20 and 24 h. All six horses had plasma DXM concentration above the limit of detection and five of six had plasma DXM concentrations above the LOQ for at least one sample time.
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Affiliation(s)
- S. McClure
- Midwest Equine Surgery and Sports Medicine, 2615 Eastgate Drive, Boone, IA 50036, USA
- Department of Veterinary Clinical Sciences College of Veterinary Medicine, Iowa State University, 1800 Christensen Drive, Ames, IA 50011-1134, USA
| | - C. Fenger
- Equine Integrated Medicine, PLC, 4904 Ironworks Rd., Georgetown, KY 40324, USA
| | - K. Kersh
- Department of Veterinary Clinical Sciences College of Veterinary Medicine, Iowa State University, 1800 Christensen Drive, Ames, IA 50011-1134, USA
| | - B. Brown
- Bradley Brown, private practice, 425 Sacree Rd., Shelbyville, KY 40065, USA
| | - G. Maylin
- New York Drug Testing and Research Program, Morrisville State College, 777 Warren Rd, Ithaca, NY 14853, USA
| | - W. Duer
- Duer Forensic Toxicology LLC., 1621 Gulf Blvd #102, Clearwater, FL 33767-2928, USA
| | - L Dirikolu
- Department of Comparative Biomedical Sciences, School of Veterinary Medicine, Louisiana State University, Skip Bertman Drive, Baton Rouge, LA 70803, USA
| | - K. Brewer
- Kimberly Brewer, private practice, 15775 Cypress Creek Lane, Wellington, FL 33414, USA
| | - J. Machin
- The Maxwell H. Gluck Equine Research Center, University of Kentucky, 1400 Nicholasville Rd, Lexington, KY 40503, USA
| | - T. Tobin
- The Maxwell H. Gluck Equine Research Center, University of Kentucky, 1400 Nicholasville Rd, Lexington, KY 40503, USA
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5
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Song D, Jusko WJ. Across‐species meta‐analysis of dexamethasone pharmacokinetics utilizing allometric and scaling modeling approaches. Biopharm Drug Dispos 2021; 42:191-203. [DOI: 10.1002/bdd.2266] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 01/15/2021] [Accepted: 01/27/2021] [Indexed: 12/15/2022]
Affiliation(s)
- Dawei Song
- Department of Pharmaceutical Sciences School of Pharmacy and Pharmaceutical Sciences State University of New York at Buffalo Buffalo New York USA
| | - William J Jusko
- Department of Pharmaceutical Sciences School of Pharmacy and Pharmaceutical Sciences State University of New York at Buffalo Buffalo New York USA
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6
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Knych HK, Weiner D, Arthur RM, Baden R, McKemie DS, Kass PH. Serum concentrations, pharmacokinetic/pharmacodynamic modeling, and effects of dexamethasone on inflammatory mediators following intravenous and oral administration to exercised horses. Drug Test Anal 2020; 12:1087-1101. [PMID: 32436346 DOI: 10.1002/dta.2862] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Revised: 05/13/2020] [Accepted: 05/17/2020] [Indexed: 11/10/2022]
Abstract
Corticosteroids are potent anti-inflammatory drugs and as such are commonly administered to performance and racehorses. The objectives of the current study were to describe blood and urine concentrations and the pharmacokinetics and effects on cortisol and inflammatory mediator concentrations, following intravenous and oral administration to 12 exercised horses. Horses received an intravenous administration of 40 mg of dexamethasone sodium phosphate and 20 mg of dexamethasone tablets with a 4 week washout in between administrations. Blood and urine samples were collected prior to and for up to 96 hours post drug administration. Whole blood samples were collected at various time points and challenged with lipopolysaccharide or calcium ionophore to induce ex vivo synthesis of eicosanoids. The concentrations of dexamethasone and eicosanoids were measured using LC-MS/MS and the concentrations from both routes of administration fit simultaneously using a three-compartment pharmacokinetic model. A turnover model with inhibition of Kin gave an adequate fit to the dexamethasone-cortisol PKPD data. Serum and urine dexamethasone concentrations were at the limit of quantitation at 96 and 48 hours post administration, respectively. The volume of distribution, systemic clearance, and terminal half-life was 0.907 L/kg, 7.89 mL/h/kg, and 1.34 h, respectively. The IC50 for cortisol suppression was 0.007 ng/mL. Stimulation of dexamethasone treated blood with lipopolysaccharide and calcium ionophore resulted in an inhibition of inflammatory biomarker production for a prolonged period of time post drug administration. The results of this study suggest that dexamethasone has a prolonged anti-inflammatory effect following intravenous or oral administration to horses.
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Affiliation(s)
- Heather K Knych
- K.L. Maddy Equine Analytical Pharmacology Laboratory, School of Veterinary Medicine, University of California Davis, CA, USA.,Department of Veterinary Molecular Biosciences, School of Veterinary Medicine, University of California, Davis, CA, USA
| | | | - Rick M Arthur
- School of Veterinary Medicine, University of California, Davis, CA, USA
| | - Russell Baden
- K.L. Maddy Equine Analytical Pharmacology Laboratory, School of Veterinary Medicine, University of California Davis, CA, USA
| | - Daniel S McKemie
- K.L. Maddy Equine Analytical Pharmacology Laboratory, School of Veterinary Medicine, University of California Davis, CA, USA
| | - Philip H Kass
- Department of Population Health and Reproduction, School of Veterinary Medicine, University of California, Davis, CA, USA
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7
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Ekstrand C, Bondesson U, Giving E, Hedeland M, Ingvast-Larsson C, Jacobsen S, Löfgren M, Moen L, Rhodin M, Saetra T, Ranheim B. Disposition and effect of intra-articularly administered dexamethasone on lipopolysaccharide induced equine synovitis. Acta Vet Scand 2019; 61:28. [PMID: 31221173 PMCID: PMC6585085 DOI: 10.1186/s13028-019-0464-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Accepted: 06/13/2019] [Indexed: 11/16/2022] Open
Abstract
Background Dexamethasone is used for the intra-articular route of administration in management of aseptic arthritis in horses. Despite its widespread use there is very little quantitative data of the disposition and response to dexamethasone. The aim of this study was to investigate and describe the synovial fluid and plasma dexamethasone concentration over time and to explore the relation between synovial fluid concentration and response using clinical endpoints as response biomarkers after IA injection of dexamethasone disodium salt solution in an equine model of synovitis. Results Inflammation was induced in the radiocarpal joint of six horses by injection of 2 ng lipopolysaccharide (LPS). Two hours later either saline or dexamethasone was injected in the same joint in a two treatment cross over design. Each horse was treated once with one of the six doses dexamethasone used (0.01, 0.03, 0.1, 0.3, 1 or 3 mg) and once with saline. Dexamethasone was quantified by means of UHPLC–MS/MS. Dexamethasone disposition was characterised by means of a non-linear mixed effects model. Lameness was evaluated both objectively with an inertial sensor based system and subjectively scored using a numerical scale (0–5). Joint circumference, skin temperature over the joint and rectal temperature were also recorded. The LPS-challenge induced lameness in all horses with high inter-individual variability. Dexamethasone significantly decreased lameness compared with saline. Other variables were not statistically significant different between treatments. Objective lameness scoring was the most sensitive method used in this study to evaluate the lameness response. A pharmacokinetic/pharmacodynamic model was successfully fitted to experimental dexamethasone and lameness data. The model allowed characterization of the dexamethasone synovial fluid concentration–time course, the systemic exposure to dexamethasone after intra-articular administration and the concentration–response relation in an experimental model of synovitis. Conclusions The quantitative data improve the understanding of the pharmacology of dexamethasone and might serve as input for future experiments and possibly contribute to maintain integrity of equine sports.
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8
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Held F, Ekstrand C, Cvijovic M, Gabrielsson J, Jirstrand M. Modelling of oscillatory cortisol response in horses using a Bayesian population approach for evaluation of dexamethasone suppression test protocols. J Pharmacokinet Pharmacodyn 2019; 46:75-87. [PMID: 30673914 PMCID: PMC6394511 DOI: 10.1007/s10928-018-09617-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Accepted: 12/31/2018] [Indexed: 11/12/2022]
Abstract
Cortisol is a steroid hormone relevant to immune function in horses and other species and shows a circadian rhythm. The glucocorticoid dexamethasone suppresses cortisol in horses. Pituitary pars intermedia dysfunction (PPID) is a disease in which the cortisol suppression mechanism through dexamethasone is challenged. Overnight dexamethasone suppression test (DST) protocols are used to test the functioning of this mechanism and to establish a diagnosis for PPID. However, existing DST protocols have been recognized to perform poorly in previous experimental studies, often indicating presence of PPID in healthy horses. This study uses a pharmacokinetic/pharmacodynamic (PK/PD) modelling approach to analyse the oscillatory cortisol response and its interaction with dexamethasone. Two existing DST protocols were then scrutinized using model simulations with particular focus on their ability to avoid false positive outcomes. Using a Bayesian population approach allowed for quantification of uncertainty and enabled predictions for a broader population of horses than the underlying sample. Dose selection and sampling time point were both determined to have large influence on the number of false positives. Advice on pitfalls in test protocols and directions for possible improvement of DST protocols were given. The presented methodology is also easily extended to other clinical test protocols.
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Affiliation(s)
- Felix Held
- Fraunhofer-Chalmers Centre, Chalmers Science Park, Gothenburg, Sweden.
- Department of Mathematical Sciences, Chalmers University of Technology and University of Gothenburg, Gothenburg, Sweden.
| | - Carl Ekstrand
- Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Marija Cvijovic
- Department of Mathematical Sciences, Chalmers University of Technology and University of Gothenburg, Gothenburg, Sweden
| | - Johan Gabrielsson
- Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Mats Jirstrand
- Fraunhofer-Chalmers Centre, Chalmers Science Park, Gothenburg, Sweden
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9
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Ekstrand C, Falkenö U, Kallings P, Tvedten H, Lilliehöök I. Plasma Dexamethasone Concentration in Relation to Glucose Response in the Horse. J Equine Vet Sci 2019. [DOI: 10.1016/j.jevs.2018.11.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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10
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Giaccone V, Macaluso A, Cammilleri G, Vella A, Ferrantelli V. Corticosteroids in liver and urine in Sicilian cattle by a LC-MS/MS method. FOOD ADDITIVES & CONTAMINANTS. PART B, SURVEILLANCE 2018; 11:201-207. [PMID: 29716443 DOI: 10.1080/19393210.2018.1470578] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The presence of corticosteroid residues was assessed in urine and liver samples from livestock of Sicily. A total of 630 bovine samples were collected from farms and slaughterhouses. The samples were analysed using solid-phase extraction (SPE) coupled with ultra-performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS). All the corticosteroids found were under the maximum residue limit imposed by Commission Regulation (EC) 37/2010. About 4% of liver samples showed dexamethasone levels above the limit of detection (LOD), with a mean of 1.5 ± 0.2 µg kg-1. Betamethasone was found only in seven liver samples, with a mean of 1.6 ± 0.1 µg kg-1. Furthermore, prednisolone and prednisone were found only in urine and liver samples from slaughterhouse, probably related to the high rate of stress for bovines. These results suggest good control practices adopted by Sicilian farms, able to ensure the quality of food products.
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Affiliation(s)
- Vita Giaccone
- a Area Chimica e Tecnologie Alimentari , Istituto Zooprofilattico Sperimentale della Sicilia "A. Mirri" , Palermo , Italy
| | - Andrea Macaluso
- a Area Chimica e Tecnologie Alimentari , Istituto Zooprofilattico Sperimentale della Sicilia "A. Mirri" , Palermo , Italy
| | - Gaetano Cammilleri
- a Area Chimica e Tecnologie Alimentari , Istituto Zooprofilattico Sperimentale della Sicilia "A. Mirri" , Palermo , Italy
| | - Antonio Vella
- a Area Chimica e Tecnologie Alimentari , Istituto Zooprofilattico Sperimentale della Sicilia "A. Mirri" , Palermo , Italy
| | - Vincenzo Ferrantelli
- a Area Chimica e Tecnologie Alimentari , Istituto Zooprofilattico Sperimentale della Sicilia "A. Mirri" , Palermo , Italy
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11
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Ponchon B, Zhao X, Ollier S, Lacasse P. Relationship between glucocorticoids and prolactin during mammary gland stimulation in dairy cows. J Dairy Sci 2016; 100:1521-1534. [PMID: 28012629 DOI: 10.3168/jds.2016-11490] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2016] [Accepted: 11/06/2016] [Indexed: 11/19/2022]
Abstract
The objectives of this study were to determine the role of glucocorticoids in the regulation of prolactin (PRL) release induced by mammary gland stimulation and to investigate whether the milk depression induced by glucocorticoids in dairy cows is due to a decrease in PRL release. In experiment 1, 8 dairy cows were used in a 4 × 4 Latin square design. Four hours after the morning milking, the cows received 1 of the following treatments: (1) a 5-min manual stimulation of the mammary gland; (2) an i.v. injection of 1 mg of dexamethasone; (3) 2 infusions of 2.5 g of metyrapone (an inhibitor of cortisol biosynthesis) in the omasum 4 and 2 h before a 5-min stimulation of the mammary gland; or (4) no treatment. Sixty minutes later, the mammary gland of each cow was stimulated for 5 min. Blood samples were collected from 20 min before to 120 min after the start of the treatment. When the mammary gland was stimulated twice in 60 min, less PRL and cortisol were released during the second stimulation. Metyrapone did not affect PRL or cortisol release. Dexamethasone decreased serum cortisol concentration but did not affect PRL concentration. In experiment 2, 16 cows were used in a crossover experimental design consisting of 2 experimental weeks separated by 1 resting week. During the first week, cows were treated as follows: (1) 4 cows were injected with 0.5 g of domperidone (a PRL secretagogue) in canola oil on d 1 and 2 and 20 mg of dexamethasone on d 1; (2) 4 cows were injected with 0.5 g of domperidone on d 1 and 2; (3) 4 cows were injected with canola oil on d 1 and 2 and with 20 mg of dexamethasone on d 1; and (4) 4 cows were injected with canola oil on d 1 and 2. During the second experimental week, the same 4 treatments were repeated, except the cows that did not receive dexamethasone in the first week received it on d 1 of the second week, and cows that did receive it in the first week did not receive it in the second week. On d 1 and 2 of each week, blood samples were collected during morning milking for PRL determination. Dexamethasone reduced milk production and decreased both basal and milking-induced PRL release. It also increased milk fat and protein percentages and decreased milk lactose content. Domperidone increased basal PRL levels in serum and milk but did not affect milk yield. Although we cannot rule out the possibility that inhibition of PRL secretion or reduction of mammary gland PRL responsiveness play a role in the inhibition of milk production by glucocorticoids, the fact that enhancement of PRL secretion by domperidone could not prevent the depression of milk yield suggests that other mechanisms are involved.
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Affiliation(s)
- B Ponchon
- Department of Animal Science, McGill University, Sainte-Anne-de-Bellevue, QC, H9X 3V9, Canada
| | - X Zhao
- Department of Animal Science, McGill University, Sainte-Anne-de-Bellevue, QC, H9X 3V9, Canada
| | - S Ollier
- Sherbrooke Research and Development Centre, Agriculture and Agri-Food Canada, Sherbrooke, QC, J1M 0C8, Canada
| | - P Lacasse
- Sherbrooke Research and Development Centre, Agriculture and Agri-Food Canada, Sherbrooke, QC, J1M 0C8, Canada.
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12
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Cuming RS, Groover ES, Wooldridge AA, Caldwell FJ. Review of glucocorticoid therapy in horses. Part 1: Pharmacology. EQUINE VET EDUC 2016. [DOI: 10.1111/eve.12555] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- R. S. Cuming
- J. T. Vaughan Large Animal Teaching Hospital Auburn University Alabama USA
| | - E. S. Groover
- J. T. Vaughan Large Animal Teaching Hospital Auburn University Alabama USA
| | - A. A. Wooldridge
- J. T. Vaughan Large Animal Teaching Hospital Auburn University Alabama USA
| | - F. J. Caldwell
- J. T. Vaughan Large Animal Teaching Hospital Auburn University Alabama USA
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13
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Ekstrand C, Ingvast-Larsson C, Olsén L, Hedeland M, Bondesson U, Gabrielsson J. A quantitative approach to analysing cortisol response in the horse. J Vet Pharmacol Ther 2015; 39:255-63. [PMID: 26542753 DOI: 10.1111/jvp.12276] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2015] [Accepted: 09/26/2015] [Indexed: 11/28/2022]
Abstract
The cortisol response to glucocorticoid intervention has, in spite of several studies in horses, not been fully characterized with regard to the determinants of onset, intensity and duration of response. Therefore, dexamethasone and cortisol response data were collected in a study applying a constant rate infusion regimen of dexamethasone (0.17, 1.7 and 17 μg/kg) to six Standardbreds. Plasma was analysed for dexamethasone and cortisol concentrations using UHPLC-MS/MS. Dexamethasone displayed linear kinetics within the concentration range studied. A turnover model of oscillatory behaviour accurately mimicked cortisol data. The mean baseline concentration range was 34-57 μg/L, the fractional turnover rate 0.47-1.5 1/h, the amplitude parameter 6.8-24 μg/L, the maximum inhibitory capacity 0.77-0.97, the drug potency 6-65 ng/L and the sigmoidicity factor 0.7-30. This analysis provided a better understanding of the time course of the cortisol response in horses. This includes baseline variability within and between horses and determinants of the equilibrium concentration-response relationship. The analysis also challenged a protocol for a dexamethasone suppression test design and indicated future improvement to increase the predictability of the test.
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Affiliation(s)
- C Ekstrand
- Department of Biomedical Sciences and Veterinary Public Health, Division of Pharmacology and Toxicology, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - C Ingvast-Larsson
- Department of Biomedical Sciences and Veterinary Public Health, Division of Pharmacology and Toxicology, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - L Olsén
- Department of Biomedical Sciences and Veterinary Public Health, Division of Pharmacology and Toxicology, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - M Hedeland
- Department of Chemistry, Environment and Feed Hygiene, National Veterinary Institute (SVA), Uppsala, Sweden.,Department of Medicinal Chemistry, Division of Analytical Pharmaceutical Chemistry, Uppsala University, Uppsala, Sweden
| | - U Bondesson
- Department of Chemistry, Environment and Feed Hygiene, National Veterinary Institute (SVA), Uppsala, Sweden.,Department of Medicinal Chemistry, Division of Analytical Pharmaceutical Chemistry, Uppsala University, Uppsala, Sweden
| | - J Gabrielsson
- Department of Biomedical Sciences and Veterinary Public Health, Division of Pharmacology and Toxicology, Swedish University of Agricultural Sciences, Uppsala, Sweden
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14
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Castagnetti C, Mariella J. Anti-inflammatory Drugs in Equine Neonatal Medicine. Part II: Corticosteroids. J Equine Vet Sci 2015. [DOI: 10.1016/j.jevs.2015.02.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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15
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Ekstrand C, Bondesson U, Gabrielsson J, Hedeland M, Kallings P, Olsén L, Ingvast-Larsson C. Plasma concentration-dependent suppression of endogenous hydrocortisone in the horse after intramuscular administration of dexamethasone-21-isonicotinate. J Vet Pharmacol Ther 2014; 38:235-42. [DOI: 10.1111/jvp.12175] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2014] [Accepted: 09/15/2014] [Indexed: 11/28/2022]
Affiliation(s)
- C. Ekstrand
- Division of Pharmacology and Toxicology; Department of Biomedical Sciences and Veterinary Public Health; Swedish University of Agricultural Sciences; Uppsala Sweden
| | - U. Bondesson
- Department of Chemistry, Environment and Feed Hygiene; National Veterinary Institute; Uppsala Sweden
- Division of Analytical Pharmaceutical Chemistry; Department of Medicinal Chemistry; Uppsala University; Uppsala Sweden
| | - J. Gabrielsson
- Division of Pharmacology and Toxicology; Department of Biomedical Sciences and Veterinary Public Health; Swedish University of Agricultural Sciences; Uppsala Sweden
| | - M. Hedeland
- Department of Chemistry, Environment and Feed Hygiene; National Veterinary Institute; Uppsala Sweden
- Division of Analytical Pharmaceutical Chemistry; Department of Medicinal Chemistry; Uppsala University; Uppsala Sweden
| | - P. Kallings
- Swedish-Norwegian Foundation for Equine Research; Stockholm Sweden
- Swedish Trotting Association; Stockholm Sweden
| | - L. Olsén
- Division of Pharmacology and Toxicology; Department of Biomedical Sciences and Veterinary Public Health; Swedish University of Agricultural Sciences; Uppsala Sweden
| | - C. Ingvast-Larsson
- Division of Pharmacology and Toxicology; Department of Biomedical Sciences and Veterinary Public Health; Swedish University of Agricultural Sciences; Uppsala Sweden
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16
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Ferranti C, Famele M, Palleschi L, Bozzetta E, Pezzolato M, Draisci R. Excretion profile of corticosteroids in bovine urine compared with tissue residues after therapeutic and growth-promoting administration of dexamethasone. Steroids 2013; 78:803-12. [PMID: 23684526 DOI: 10.1016/j.steroids.2013.05.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/30/2012] [Revised: 04/11/2013] [Accepted: 05/06/2013] [Indexed: 10/26/2022]
Abstract
The illicit use of dexamethasone as growth-promoting agent in animal breeding is still practiced within the EU constituting a health risk for meat consumers. An experimental study was developed to assess dexamethasone urinary excretion and tissue distribution (liver, kidney, and muscle) in male calves after therapeutic and growth-promoting administration. Urine and tissue samples collected from treated and untreated bovines were also investigated for the presence of other natural and synthetic corticosteroids (prednisolone, prednisone, hydrocortisone, and cortisone), in order to study a possible correlation with dexamethasone administration and to clarify prednisolone origin. Analyses were performed by a multi-residue LC-MS/MS method developed and validated according to the Commission Decision 2002/657/EC. The results confirm the rapid rate of dexamethasone urinary excretion, irrespective of the dosage, the duration and the route of administration, and the disappearance of cortisone and hydrocortisone during the treatment. Dexamethasone was distributed to the tissues where the elimination rate proceeded relatively slower as suggested by the presence of residues one month after the withdrawal of the therapeutic treatment. An increase in the number of positive findings for prednisolone, in association with higher levels of cortisone and hydrocortisone, was observed in urine samples collected from slaughterhouse rather than those collected at the farm. Prednisone residues were found only in one urine sample that showed the highest levels of prednisolone, hydrocortisone, and cortisone. The occurrence of prednisolone residues in urine and even in tissue samples confirms the endogenous nature of this molecule.
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Affiliation(s)
- Carolina Ferranti
- Istituto Superiore di Sanità, Viale Regina Elena 299, 00161 Roma, Italy.
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17
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Pharmacokinetics of dexamethasone after intravenous and intramuscular administration in broiler chickens. Vet J 2013; 195:216-20. [DOI: 10.1016/j.tvjl.2012.06.026] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2011] [Revised: 06/06/2012] [Accepted: 06/18/2012] [Indexed: 12/20/2022]
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18
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SOMA LR, UBOH CE, LIU Y, LI X, ROBINSON MA, BOSTON RC, COLAHAN PT. Pharmacokinetics of dexamethasone following intra-articular, intravenous, intramuscular, and oral administration in horses and its effects on endogenous hydrocortisone. J Vet Pharmacol Ther 2012; 36:181-91. [DOI: 10.1111/j.1365-2885.2012.01412.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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19
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Hart KA, Dirikolu L, Ferguson DC, Norton NA, Barton MH. Daily endogenous cortisol production and hydrocortisone pharmacokinetics in adult horses and neonatal foals. Am J Vet Res 2012; 73:68-75. [DOI: 10.2460/ajvr.73.1.68] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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20
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Soma LR, Uboh CE, You Y, Guan F, Boston RC. Pharmacokinetics of intra-articular, intravenous, and intramuscular administration of triamcinolone acetonide and its effect on endogenous plasma hydrocortisone and cortisone concentrations in horses. Am J Vet Res 2011; 72:1234-42. [DOI: 10.2460/ajvr.72.9.1234] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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21
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Ferranti C, Quadri FD, Palleschi L, Marchiafava C, Pezzolato M, Bozzetta E, Caramelli M, Draisci R. Studies on the presence of natural and synthetic corticosteroids in bovine urine. Steroids 2011; 76:616-25. [PMID: 21382393 DOI: 10.1016/j.steroids.2011.02.044] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/14/2010] [Revised: 02/25/2011] [Accepted: 02/26/2011] [Indexed: 10/18/2022]
Abstract
Natural and synthetic corticosteroids are widely used in veterinary medicine for their anti-inflammatory properties, but are also illegally used in animal breeding as growth-promoting agents: this latter application in livestock production has been banned within the European Union due to health concerns for the consumer. In this work urine samples collected from bovines experimentally treated with dexamethasone (0.4 mg of dexamethasone 21-disodium phosphate per capita/day for 20 consecutive days) and bovines bred under strictly controlled conditions were investigated for the presence of natural and synthetic corticosteroids, using a simple multi-residue liquid chromatography-tandem mass spectrometry method, developed and validated in accordance with the criteria of the Commission Decision 2002/657/EC. The aim of this work is to investigate the effect of a low dosage and long term dexamethasone treatment on the levels of endogenous corticosteroids in cattle and to evaluate the possible presence of prednisolone residues in bovines bred under strictly controlled conditions. Our findings confirm the high and rapid rate of dexamethasone urinary excretion. Dexamethasone treatment elicited an early reduction of hydrocortisone and cortisone, suggesting the disappearance of these two hormones as an indirect indicator of corticosteroid treatment in cattle. Prednisolone residues were found (concentration interval 0.4-1.4 ngmL(-1)) in urine samples collected from control bovines especially at the slaughterhouse, together with high levels of hydrocortisone and cortisone. Further studies are necessary to find out the reason of unexplained excretion of this hormone in urine samples of untreated bovines.
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Affiliation(s)
- Carolina Ferranti
- Istituto Superiore di Sanità, Viale Regina Elena 299, 00161 Roma, Italy.
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22
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Grady JA, Davis EG, Kukanich B, Sherck AB. Pharmacokinetics and pharmacodynamics of dexamethasone after oral administration in apparently healthy horses. Am J Vet Res 2010; 71:831-9. [PMID: 20594087 DOI: 10.2460/ajvr.71.7.831] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To assess pharmacokinetic and pharmacodynamic properties of dexamethasone administered PO as a solution or powder, compared with properties of dexamethasone solution administered IV, in apparently healthy horses. ANIMALS 6 adult horses. PROCEDURES Serum cortisol concentration for each horse was determined before each treatment (baseline values). Dexamethasone (0.05 mg/kg) was administered PO (in solution or powdered form) or IV (solution) to horses from which feed had or had not been withheld (unfed and fed horses, respectively). Each horse received all 6 treatments in random order at 2-week intervals; PO and IV administrations of dexamethasone were accompanied by IV or PO sham treatments, respectively. Plasma dexamethasone and serum cortisol concentrations were assessed at predetermined intervals. RESULTS Maximum plasma dexamethasone concentration after PO administration of powdered dexamethasone in unfed horses was significantly higher than the maximum plasma concentration after PO administration of dexamethasone solution in unfed or fed horses. Mean bioavailability of dexamethasone ranged from 28% to 66% but was not significantly different among horses receiving either formulation PO in the unfed or fed state. After dexamethasone treatment PO or IV, serum cortisol concentrations were significantly less than baseline at 1 to 72 hours in unfed horses and at 2 to 48 hours in fed horses. CONCLUSIONS AND CLINICAL RELEVANCE PO or IV administration of dexamethasone resulted in suppression of cortisol secretion in unfed and fed adult horses; the magnitude of suppression did not differ among treatment groups, and serum cortisol concentrations returned to baseline after 48 to 72 hours.
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Affiliation(s)
- Jason A Grady
- Veterinary Medical Teaching Hospital, College of Veterinary Medicine, Kansas State University, Manhattan, KS 66506, USA.
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23
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Sojka J, Jedra U, Hester N, Jackson LP, Juarez A. Topical Dexamethasone and Dimethyl Sulfoxide Solutions Do Not Result in Detectable Blood Levels of Dexamethasone. J Equine Vet Sci 2008. [DOI: 10.1016/j.jevs.2008.10.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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24
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Soma LR, Uboh CE, Luo Y, Guan F, Moate PJ, Boston RC. Pharmacokinetics of methylprednisolone acetate after intra-articular administration and its effect on endogenous hydrocortisone and cortisone secretion in horses. Am J Vet Res 2006; 67:654-62. [PMID: 16579759 DOI: 10.2460/ajvr.67.4.654] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To determine the pharmacokinetics of methylprednisolone (MP) and develop a pharmacokinetic-pharmacodynamic model of the related changes in plasma concentrations of endogenous hydrocortisone (HYD) and cortisone (COR) following intra-articular administration of methylprednisolone acetate (MPA) in horses. ANIMALS 6 Thoroughbreds. PROCEDURES In each horse, 200 mg of MPA was injected intrasynovially into a carpal joint, and plasma MP, HYD, and COR concentrations were determined via liquid chromatography-mass spectrometry. RESULTS A 5-compartment pharmacokinetic-pharmacodynamic model was used to describe the concatenated changes in the plasma concentrations of MP, HYD, and COR and to estimate the instantaneous rate of endogenous HYD production. The median transfer half-life (t(1/2t)) of methylprednisolone from the joint to plasma and elimination half-life (t(1/2e)) from plasma were 1.7 and 19.2 hours, respectively. Maximum plasma concentration of methylprednisolone was 7.26 +/- 3.3 ng/mL at 8 hours, which decreased to 0.11 +/- 0.08 ng/mL at 144 hours after injection. At 3 hours after MPA administration, plasma COR and HYD concentrations were significantly decreased from baseline values (from 2.9 +/- 0.28 ng/mL to 2.10 +/- 1.0 ng/mL and from 61.1 +/- 18.9 ng/mL to 25.7 +/- 12.1 ng/mL, respectively). CONCLUSIONS AND CLINICAL RELEVANCE The sensitivity of the analytic method used allowed complete description of the related kinetics of MP, HYD, and COR following intra-articular administration of MPA. A single intra-articular administration of MPA profoundly affected the secretion of HYD and COR in horses; secretion of endogenous corticosteroids remained suppressed for as long as 240 hours after injection.
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Affiliation(s)
- Lawrence R Soma
- New Bolton Center Campus, School of Veterinary Medicine, University of Pennsylvania, Kennett Square, PA 19348, USA
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25
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Luo Y, Uboh CE, Soma LR, Guan F, Rudy JA, Tsang DS. Resolution, quantification and confirmation of betamethasone and dexamethasone in equine plasma by liquid chromatography/tandem mass spectrometry. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2005; 19:825-832. [PMID: 15714597 DOI: 10.1002/rcm.1851] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
This method describes the simultaneous separation, identification, quantification and confirmation of betamethasone (BTM) and dexamethasone (DXM) in equine plasma by liquid chromatography (LC) integrated with multidimensional tandem mass spectrometry. Analytes were directly extracted from equine plasma by methyl tert-butyl ether (MTBE). The residues were reconstituted with sample solvent. LC separation of the analytes was performed on a Hypercarb column using acetonitrile/water/formic acid (95:5:0.5, v/v/v) as the mobile phase. Sample screening, quantification and confirmation were performed in multiple reaction monitoring (MRM) mode. The method was linear over the concentration range of 0.1-75 ng/mL for both analytes. Limit of detection (LOD) was 50 pg/mL and that of quantification (LOQ) was 100 pg/mL for both analytes. The limit of confirmation (LOC) for the presence of BTM or DXM by MRM was 0.5 ng/mL. The intra-and inter-day precisions expressed as coefficient of variation (CV) for quantification of DXM and BTM from 0.1 to 50 ng/mL were less than 7% and the accuracy was in the range of 97-105%. This method is capable of distinguishing BTM from DXM when both analytes are simultaneously present in equine plasma. Measurement uncertainty for both analytes was estimated at less than 16%. The method is rapid, specific, selective, sensitive, simple and reliable. The importance of this method is its usefulness in directly identifying and differentiating BTM from DXM without derivatization.
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Affiliation(s)
- Yi Luo
- University of Pennsylvania, School of Veterinary Medicine, Department of Clinical Studies, New Bolton Center Campus, Kennett Square, PA 19348, USA
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26
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Luo Y, Uboh CE, Soma LR, Guan FY, Rudy JA, Tsang DS. Simultaneous analysis of twenty-one glucocorticoids in equine plasma by liquid chromatography/tandem mass spectrometry. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2005; 19:1245-1256. [PMID: 15838928 DOI: 10.1002/rcm.1916] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
A method for the simultaneous separation, identification, quantification and confirmation of the presence of 21 glucocorticoids (GCC) in equine plasma by liquid chromatography coupled with triple stage quadrupole tandem mass spectrometry (LC/TSQ-MS/MS) is described. Plasma sample augmented with the 21 GCC was extracted with methyl tert-butyl ether (MTBE) and analyzed by positive electrospray ionization. Desoxymetasone or dichlorisone acetate was used as the internal standard (IS). Quantification was performed by IS calibration. For each drug, one major product ion was chosen and used for screening for that drug. Analyte confirmation was performed by using the three most intense product ions formed from the precursor ion and the corresponding mass ratios. The recovery of the 21 GCC when spiked into blank plasma at 5 ng/mL was 45-200% with coefficient of variation (CV) from 0.3-18%. The limit of detection (LOD) and that of quantification (LOQ) for most of the analytes were 50-100 pg/mL and 1 ng/mL, respectively, whereas that of confirmation (LOC) was 100-300 pg/mL depending on the analyte. Intra- and inter-day precisions expressed as CV for quantification of 1 and 10 ng/mL was 1.0-17%, and 0.51-19%, respectively, and the accuracy was from 84-110%. The linear concentration range for quantification was 0.1-100 ng/mL (r(2) > 0.997). Estimated measurement uncertainty was from 11-37%. This study was undertaken to develop a method for simultaneous screening, identification, quantification and confirmation of these agents in post-race equine plasma samples. The method has been successfully applied to screening of a large number of plasma samples obtained from racehorses in competition and in pharmacokinetic studies of dexamethasone in the horse and concurrent changes in endogenous GCC, hydrocortisone and cortisone. The method is simple, sensitive, selective and reliably reproducible.
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Affiliation(s)
- Y Luo
- University of Pennsylvania, School of Veterinary Medicine, Department of Clinical Studies, New Bolton Center Campus, Kennett Square, 19348, USA
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