Redig P T, Larson A A, Duke G E
Am J Vet Res. 1984 Jan;45(1):125-7.
The relative anesthetic effects of the 2 purified isomers and the racemic mixture of ketamine were compared in 6 great horned owls (Bubo virginianus), a species in which racemic ketamine is poorly tolerated. Other investigators have reported that the L(-) form is only a 3rd as potent as the D(+) form with respect to analgesic action in mammals. Accordingly, the racemic and the - forms were given at 2 X and 3 X, respectively, the dose of the + form in an attempt to achieve a potentially equivalent state of anesthesia. At these dose levels, there was no difference observed in the average duration of anesthesia with the 3 ketamine preparations. The - isomer yielded a poorer anesthetic response characterized by inadequate muscle relaxation, cardiac arrhythmias, and marked excitatory behavior during recovery. With the dosages used, the + form and the racemate were comparable in degree of muscle relaxation produced. The + form yielded smoother inductions and less cardiac arrhythmia than did the racemate.
在6只大角鸮（Bubo virginianus）中比较了氯胺酮2种纯化异构体及外消旋混合物的相对麻醉效果，大角鸮对外消旋氯胺酮耐受性较差。其他研究人员报告称，就对哺乳动物的镇痛作用而言，L(-) 型的效力仅为D(+) 型的三分之一。因此，分别给予外消旋体和L(-) 型2倍和3倍于D(+) 型的剂量，试图达到潜在的等效麻醉状态。在这些剂量水平下，3种氯胺酮制剂的平均麻醉持续时间没有差异。L(-) 异构体产生的麻醉反应较差，表现为肌肉松弛不足、心律失常以及恢复过程中明显的兴奋行为。在所使用的剂量下，D(+) 型和外消旋体产生的肌肉松弛程度相当。D(+) 型诱导过程比外消旋体更平稳，心律失常更少。
