Effects of pretreatment with ketoprofen and phenylbutazone on experimentally induced synovitis in horses.

This research investigates how two nonsteroidal anti-inflammatory drugs – Ketoprofen and Phenylbutazone – impact inflammation in horse joints. The study found that Phenylbutazone was more effective in reducing symptoms of inflammation.

Research Methodology

• The experiment involved four groups of six horses, which received either the nonsteroidal anti-inflammatory drugs (NSAID) ketoprofen and phenylbutazone, or a saline solution in a randomized configuration.
• The horses involved in the study were clinically normal mares and geldings.
• To create inflammation experimentally, the researchers injected the horse’s left intercarpal joints with sterile carrageenan at the same instance as the administration of NSAID or saline solution.
• Numerous parameters were observed and measurements were taken at specific intervals: at 0, 1, 3, 6, 9, 12, 24, and 48 hours. These parameters included clinical assessments and synovial fluid withdrawal.

Research Findings

• Following the induction of inflammation, increases were noted in the synovial fluid of the eicosanoids: Prostaglandin E2 (PGE2) and leukotriene B4. However, by the 48 hours mark, levels were found to have almost returned to their initial, baseline levels.
• All horses treated with NSAID had decreased PGE2 compared to those treated with saline solution. Phenylbutazone-treated horses maintained this effect for a longer duration than those treated with Ketoprofen.
• The treatment showed no effect on levels of leukotriene B4.
• In the horses treated with saline, an increase in lameness, joint temperature, and synovial fluid characteristics such as volume, protein concentration, and nucleated cells were observed from 3 to 12 hours post-induction. These indicators were markedly reduced by the 48-hour mark.
• Only Phenylbutazone was found to diminish lameness, joint temperature and synovial fluid volume.

Conclusions

• The study revealed that Phenylbutazone was more effective than Ketoprofen in reducing the primary symptoms of inflammation – such as lameness, elevated joint temperature, and synovial fluid alterations.
• The results did not show any evidence to suggest that either NSAID inhibits lipoxygenase.
• The researchers concluded that the experimental model used to induce inflammation in the horse’s joint effectively mimics the synovial fluid alterations observed in horses with septic arthritis. They also suggest that Phenylbutazone could be more beneficial than Ketoprofen in managing acute joint inflammation in horses.