Analgesic Effect of the Mint Terpenoid L-Carvone in Sheep

ObjectiveTo determine whether L-carvone increases the voltage threshold response to a noxious electrical stimulus in sheep.Study DesignProspective, blinded, randomized, crossover experimental study.AnimalsA group of six healthy adult sheep.MethodsSheep were instrumented with cranial dorsothoracic subcutaneous copper electrodes. A stimulator delivered 10 ms square wave at 50 pps starting 0.1 V 0.2 V/s ramp. The stopped once two observers who blinded treatment noted behavioral pain or when 15 cut-off was reached. Next, 0.15 mL kg−1 either 50% solution saline-vehicle control administered intramuscularly, and responses measured every 5-to-15 min over 6-hour period using methods identical baseline. One week following first (L-carvone control), sheep studied second (control L-carvone). Drug time effects evaluated two-way repeated-measures ANOVA, pairwise comparisons Holm-Sidák tests values p < 0.05 considered significant.ResultsL-carvone significantly increased for most points up 75 minutes compared baseline saline control. last point different between treatments 5 hours after drug administration. decreased several 3 hours.ConclusionsAnd Clinical Relevance Intramuscular is analgesic sheep, although ethanol-propylene glycol vehicle may cause mild hyperalgesia. This study demonstrates that food-derived compound can be used relieve food-producing animal.