Development of an intra-lamellar microdialysis method for laminitis investigations in horses.

This research developed and tested a method for continuous monitoring of fluid in horse lamellar tissue. This technique could help to understand and treat laminitis, a debilitating hoof disease in horses.

Research Methodology

• The research made use of microdialysis (MD) technology, a method for sampling small amounts of fluid from living organisms in real time.
• The researchers inserted microdialysis probes into the soft tissue (lamellae) within horses’ hooves under local anaesthesia.
• The test subject for this experimental setup was six healthy Standardbred horses.

Experiment Procedure

• The horses were given an intravenous injection of gentamicin, an antibiotic known to have interesting diffusion properties across different types of tissue.
• After the injection, researchers collected and analysed microdialysis and serum samples from the horses over a period of 24 hours.
• Samples were analysed using a sensitive ELISA test for the presence and concentration of gentamicin, and a fluorescence polarization immunoassay for urea concentrations. Urea is a common waste product in the body, and its concentration can help to calibrate the probes and validate the data.
• The probes’ performance was validated by comparing the expected recovery of urea and gentamicin (as per the in vitro experiment) and the actual recovery in the in vivo environment.

Results & Conclusion

• The researchers found that the concentration of gentamicin was significantly higher in serum than in the lamellar extracellular fluid, which is expected due to the properties of this antibiotic.
• Interestingly, the drug remained above the minimum inhibitory concentration (MIC) in the lamellae extracellular fluid for 4 hours longer than in the bloodstream, indicating a slower diffusion and release rate in this tissue.
• The research concludes that this technique can be a valuable tool to monitor changes in the extracellular fluid of the lamellae during laminitis and to study the local kinetics of drugs used therapeutically for this condition.