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Iontophoresis of dexamethasone-phosphate into the equine tibiotarsal joint


, : Iontophoresis of dexamethasone-phosphate into the equine tibiotarsal joint. Journal of Veterinary Pharmacology and Therapeutics 23(4): 229-236

In human rehabilitation medicine, dexamethasone-phosphate is theoretically iontophoresed to localized subcutaneous tissue where conversion to dexamethasone occurs. This delivery system has recently been introduced into veterinary medicine for the same purpose. However, the pharmacokinetic justification for parenteral delivery of this prodrug remains undocumented. Utilizing iontophoretic methods that are relevant to both human and veterinary clinical practice, the present investigation compared injection and iontophoresis of dexamethasone-phosphate into the equine tibiotarsal joint, also known as the tarsocrual joint. The tibiotarsal joints of seven horses were injected with 4 mL of 6 mg/mL dexamethasone-phosphate. With a similar drug concentration and over the same application site, six different horses underwent simultaneous cathodic iontophoresis (4 mA, 40 min) or passive application (0 mA, 40 min) on contralateral limbs. Following all applications, tibiotarsal joint synovium was collected. Local venous blood samples were also collected from the iontophoretic and passive application sites for analysis of plasma drug concentrations. Because of the potential for conversion of dexamethasone-phosphate to dexamethasone, an extraction and analysis protocol was developed for both chemicals. The technique demonstrated a linear range of detection (0.39-12 microg/mL) and a capability for measuring both chemicals in plasma and synovium. Conversion of dexamethasone-phosphate to dexamethasone occurred during synovial incubation (37 degrees C) and following freeze-thaw cycles. In contrast to the measurable synovial concentrations of dexamethasone-phosphate (2.3 +/- 0.96 mg/mL) and dexamethasone (0.27 +/- 0.07 mg/mL) following injection, neither drug was detected in the synovium or the local venous blood following iontophoretic or passive applications. In conclusion, these results do not confirm iontophoretic or passive delivery of measurable dexamethasone-phosphate into the tibiotarsal joint using current clinical methods.

US$19.90

PMID: 11106997

DOI: 10.1046/j.1365-2885.2000.t01-2-00279.x


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Gorter, J.A.; Brady, R.J., 1995: Modulation of N-methyl-D-aspartic acid receptors by extracellular calcium in immature and adult hippocampal slices: Whole cell recordings in CA3 pyramidal cells. Lowering extracellular calcium concentration (Ca-2+)-o in rat hippocampal slices can lead to an induction of epileptiform activity. It has been shown that this effect is more pronounced in slices of neonatal rats (postnatal day, PND 8-19) than in...

Chapman, H.D., 1969: Proc. First Int. Citrus Symposium, Univ. Calif., Riverside, 16-26 Mar., 1968. A comment on the papers presented at this symposium has been noted . The subjects discussed in some of the sections are summarized below. a. Air pollution C. R. THOMPSON (705), W. M. DUGGER & R. L. PALMER (711), R. F. BREWER (729) and O. C. TAYLOR...

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Luneburg, Rudolf K., 1947: Mathematical analysis of binocular visio. This treatise may become the foundation for a new concept of binocular vision and space perception. It provides a metric for the visual space sense and contributes to our knowledge of binocular vision in general. Luneburg's investigation has...

Martín, J.F.; Casqueiro, J.; Liras, P., 2005: Secretion systems for secondary metabolites: how producer cells send out messages of intercellular communication. Many secondary metabolites (e.g. antibiotics and mycotoxins) are toxic to the microorganisms that produce them. The clusters of genes that are responsible for the biosynthesis of secondary metabolites frequently contain genes for resistance to the...