Detomidine reduces the plasma catecholamine, but not cortisol concentrations in horses.

The research investigates the effects of the drug detomidine on horses, revealing that it lowers plasma catecholamine concentrations, but has no effect on cortisol levels, suggesting a reduction in sympatho-adrenal activity.

Introduction

The study revolves around analyzing the effects of single doses of detomidine, an alpha 2-adrenergic sedative-analgesic drug, on the concentrations of several substances in horse plasma. These substances include adrenaline, noradrenaline, two catecholamine metabolites (3,4-dihydroxyphenylglycol and 3,4-dihydroxyphenylacetic acid), and cortisol.

Methodology

• The drug detomidine was administered intravenously to adult horses in two different dosages – 10 micrograms/kg (in seven horses) and 20 micrograms/kg (in nine horses).
• The plasma concentrations of the mentioned substances were determined before and 30 minutes after the administration of the medication.

Results

• Post-medication, a significant decrease in plasma concentrations of noradrenaline and the catecholamine metabolites was observed in the horses given both 10 micrograms/kg and 20 micrograms/kg of detomidine.
• The levels of adrenaline in the plasma also showed a tendency to decrease following the administration of the drug, although this was not deemed statistically significant.
• In contrast, the levels of cortisol, a hormone associated with stress responses, remained unaffected by the use of detomidine.

Conclusion

Based on the obtained results, it is concluded that detomidine reduces the sympatho-adrenal activity in horses. This is evident from the fact that the plasma concentrations of noradrenaline and catecholamine metabolites decreased significantly following the administration of detomidine. The lack of change in cortisol levels suggests that detomidine’s effects are specific to certain components of the stress response, rather than simply reducing stress levels overall. The findings are valuable for understanding how detomidine works and its potential impact on horses’ stress and pain responses.