Owens J G, Kamerling S G, Stanton S R, Keowen M L
Department of Veterinary Physiology, Pharmacology and Toxicology, School of Veterinary Medicine, Louisiana State University, Baton Rouge, USA.
J Pharmacol Exp Ther. 1996 Jul;278(1):179-84.
Detomidine (10, 20 and 40 micrograms/kg i.v.) and saline were administered to eight adult horses with hoof pain and lameness associated with chronic laminitis. Mechanical noxious stimulation was applied to 16 loci over the solar surface of each forefoot by means of an electronic hoof tester to determine chronic pain thresholds. Horses were evaluated before and at 25, 55 and 120 min after treatment for lameness and to determine hoof compression thresholds (HCTs), the percentage of responsive loci and the subjective grade of hoof withdrawal response at each responsive locus. Detomidine produced a dose-dependent increase in HCT and a decrease in the subjective grade of hoof withdrawal response through 55 min after treatment. At 25 and 55 min postdose, the 40 micrograms/kg dose produced maximal elevation of the HCT. The percentage of responsive loci was decreased by detomidine at 25 min in a dose-dependent manner. The lameness grade was decreased by 40 and 20 micrograms/kg of detomidine at 25 min postdose. These data support previous studies demonstrating detomidine-induced analgesia in equine models of acute nociception.
将地托咪定（10、20和40微克/千克静脉注射）和生理盐水给予八匹患有与慢性蹄叶炎相关的蹄部疼痛和跛行的成年马。通过电子蹄测试仪对每只前蹄的蹄底面16个位点施加机械性伤害性刺激，以确定慢性疼痛阈值。在治疗前以及治疗后25、55和120分钟对马匹进行跛行评估，并确定蹄部压缩阈值（HCT）、反应位点的百分比以及每个反应位点的蹄部退缩反应主观等级。地托咪定在治疗后55分钟内使HCT呈剂量依赖性增加，并且使蹄部退缩反应主观等级降低。给药后25和55分钟时，40微克/千克剂量使HCT达到最大升高。给药后25分钟时，地托咪定使反应位点的百分比呈剂量依赖性降低。给药后25分钟时，40和20微克/千克的地托咪定使跛行等级降低。这些数据支持了先前的研究，这些研究表明地托咪定在马急性伤害感受模型中可诱导镇痛作用。
