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Plasma, urine, and synovial fluid disposition of methylprednisolone acetate and isoflupredone acetate after intra-articular administration in horses.
Abstract: OBJECTIVE--To document plasma, urine, and synovial fluid disposition of 2 common intra-articularly administered steroid preparations, methylprednisolone acetate (MPA) and isoflupredone acetate (IPA). DESIGN--Descriptive investigation. SAMPLE POPULATION--100 mg of MPA or 4 mg of IPA was administered to 2 groups of 4 healthy sound radiographically normal female horses. PROCEDURE--Blood samples were collected at time 0 (before) and 2, 4, 6, 8, 10, 12, 24, 36, 48, 72, and 96 hours after administration of the designated steroid. Complete urine collection for measurement of designated steroid was accomplished by use of occluding 28-F balloon catheters. Synovial fluid samples were aseptically aspirated from the injected and contralateral uninjected tarsocrural joint at time 0 and 8, 24, 48, 240, and 672 hours after administration of the designated steroid. All samples were screened by ELISA to detect parent drug or metabolite equivalent, with a sensitivity of 2.5 ng/ml for MPA and 0.1 ng/ml for IPA. If drug was detected by ELISA in the plasma or synovial fluid, the samples were further quantified and specified, using HPLC with a lower limit of quantification (10 ng/ml). RESULTS--Between 2 and 12 hours after administration, plasma contained < 10 ng of MPA or IPA/ml (parent drug or metabolite equivalent), as intermittently detected by ELISA. Parent drug or metabolite equivalent was detected in the urine for 24 and 72 hours after injection of IPA and MPA, respectively. Synovial fluid from the contralateral joint contained no detectable MPA or IPA at any sample collection time. Median half-life for MPA, as detected by HPLC, was 10.3 hours (range, 6.1 to 10.6) in the synovial space. Median half-life for methylprednisolone, as detected by HPLC, was 10.4 (range, 9.9 to 32.1) hours. CONCLUSIONS--Both steroids appeared to be rapidly hydrolyzed to their respective ester forms, as detected by HPLC. The ELISA appeared to be a useful screening tool for detection of corticosteroids in this variety of body fluids.
Publication Date: 1996-02-01 PubMed ID: 8633806 The Equine Research Bank provides access to a large database of publicly available scientific literature. Inclusion in the Research Bank does not imply endorsement of study methods or findings by Mad Barn.
- Journal Article
- Research Support
- Non-U.S. Gov't
- Biochemistry
- Biological Half-Life
- Clinical Study
- Diagnostic Technique
- Drug
- Enzyme-Linked Immunosorbent Assay (ELISA)
- Equine Health
- High-performance Liquid Chromatography (HPLC)
- Horses
- Intra-Articular Injection
- Metabolism
- Metabolites
- Pharmacodynamics
- Pharmacokinetics
- Plasma
- Steroids
- Synovial Fluid
- Urine Analysis
- Veterinary Medicine
- Veterinary Research
Summary
This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.
The research article details an experiment that studied the behaviour and detection of two common equine steroids, methylprednisolone acetate (MPA) and isoflupredone acetate (IPA), once intra-articularly administered in horses. The study analysed their presence in different horse body fluids over a specific timing period.
Research Objective and Design
- The main objective of this research was to document the behaviour and detection of methylprednisolone acetate (MPA) and isoflupredone acetate (IPA) in equine blood, urine, and synovial fluid. These steroids were administrated intra-articularly, injected directly in the joint.
Study Sample and Procedure
- The study included two groups of four healthy sound radiographically normal female horses and each group was administered with a specific dosage of either MPA or IPA.
- Blood samples were collected at different time intervals after administering the steroids. Meanwhile, urine was collected using a special technique involving occluding 28-F balloon catheters.
- Synovial fluid samples were collected from the injected joint and the contralateral uninjected joint at predetermined times after steroid administration.
- All these samples were screened using ELISA, a test that detects parent drug or metabolite equivalent, for the presence of MPA or IPA. If the steroids were detected in the plasma or synovial fluid, the samples were further analyzed using high-performance liquid chromatography (HPLC).
Research Findings
- Between 2 and 12 hours post-administration, plasma contained less than 10 ng of MPA or IPA/ml, at times detected by the ELISA test.
- Parent drug or metabolite equivalent was detected in the urine for 24 hours after injection of IPA and up to 72 hours after injection of MPA.
- No MPA or IPA could be detected in the synovial fluid from the contralateral (not injected) joint at any time point.
- Based on HPLC measurements, the median half-life for MPA in the synovial fluid was found to be 10.3 hours, and the median half-life for methylprednisolone was approximately 10.4 hours.
- Both steroids appeared to be rapidly hydrolyzed to their respective ester forms.
Conclusions
- Based on the results, both steroids broke down swiftly into their respective ester forms as indicated by HPLC.
- ELISA proved to be a useful screening tool for detecting corticosteroids in various body fluids.
Cite This Article
APA
Lillich JD, Bertone AL, Schmall LM, Ruggles AJ, Sams RA.
(1996).
Plasma, urine, and synovial fluid disposition of methylprednisolone acetate and isoflupredone acetate after intra-articular administration in horses.
Am J Vet Res, 57(2), 187-192.
Publication
Researcher Affiliations
- Department of Veterinary Clinical Sciences, Ohio State University, Columbus 43210, USA.
MeSH Terms
- Animals
- Chromatography, High Pressure Liquid / veterinary
- Enzyme-Linked Immunosorbent Assay / veterinary
- Female
- Fluprednisolone / administration & dosage
- Fluprednisolone / analogs & derivatives
- Fluprednisolone / analysis
- Fluprednisolone / pharmacokinetics
- Glucocorticoids / administration & dosage
- Glucocorticoids / analysis
- Glucocorticoids / pharmacokinetics
- Horses / metabolism
- Injections, Intra-Articular / veterinary
- Methylprednisolone / administration & dosage
- Methylprednisolone / analogs & derivatives
- Methylprednisolone / analysis
- Methylprednisolone / pharmacokinetics
- Methylprednisolone Acetate
- Random Allocation
- Synovial Fluid / chemistry
- Synovial Fluid / metabolism
- Time Factors
Citations
This article has been cited 4 times.- 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 Jun 20;61(1):28.
- Fahey M, Mitton E, Muth E, Rosenthal AK. Dexamethasone promotes calcium pyrophosphate dihydrate crystal formation by articular chondrocytes. J Rheumatol 2009 Jan;36(1):163-9.
- Habib GS, Abu-Ahmad R. Lack of effect of corticosteroid injection at the shoulder joint on blood glucose levels in diabetic patients. Clin Rheumatol 2007 Apr;26(4):566-8.
- Yu R, Jusko WJ. Meta-Analysis and Mechanism-Based Modeling of Synovial and Plasma Pharmacokinetics and Adrenal Suppression Following Intra-Articular Injection of Methylprednisolone Acetate in Horses. J Vet Pharmacol Ther 2025 Jul;48(4):260-273.
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