Unterwald E, Sasson S, Kornetsky C
Eur J Pharmacol. 1987 Jan 20;133(3):275-81. doi: 10.1016/0014-2999(87)90023-9.
Rats were trained to escape from aversive electrical brain stimulation delivered to the midbrain reticular formation (MRF) or to obtain rewarding intracranial stimulation delivered to the medial forebrain bundle (MFB). The threshold for escape behavior was determined by a modification of the psychophysical method of limits. Likewise, reward thresholds were determined by a rate-free psychophysical method. Acute administration of ethylketocyclazocine (EKC) (0.06-1.0 mg/kg s.c.) raised escape threshold in a dose-dependent manner while having no effect on non-specific measures of sedation or motor impairment. This suggests that opioids with kappa receptor activity specifically modulate pain at a supraspinal level. Administration of EKC had no effect on the threshold for rewarding intracranial stimulation to the MFB suggesting that EKC has low potential for abuse.
训练大鼠逃避施加于中脑网状结构（MRF）的厌恶性脑电刺激，或获取施加于内侧前脑束（MFB）的颅内奖赏性刺激。逃避行为的阈值通过对极限心理物理学方法的改良来确定。同样，奖赏阈值通过无速率心理物理学方法来确定。急性给予乙基酮环唑辛（EKC）（0.06 - 1.0毫克/千克，皮下注射）以剂量依赖方式提高逃避阈值，同时对镇静或运动障碍的非特异性指标无影响。这表明具有κ受体活性的阿片类药物在脊髓上水平特异性调节疼痛。给予EKC对MFB颅内奖赏性刺激的阈值无影响，表明EKC滥用潜力低。
