Gallagher M, Meagher M W, Bostock E
Behav Neurosci. 1987 Jun;101(3):315-24. doi: 10.1037//0735-7044.101.3.315.
The effects of opiate manipulations were examined on latent inhibition of classically conditioned heart rate in rabbits. Animals were exposed to an auditory stimulus that was later used as a conditioned stimulus (CS). Administration of the agonist levorphanol into the medial septal region either preceding or immediately following CS preexposure sessions attenuated latent inhibition of the conditioned response. This effect was observed in animals that showed no change in long-term retention of habituation. Administration of levorphanol into the central nucleus of the amygdala, a sensitive site for opiate manipulations on aversive conditioning tasks, was ineffective. Further analysis of the effect obtained within the septal region revealed pharmacological specificity. The effect of posttraining levorphanol was also time dependent and exhibited neuroanatomical specificity. Posttraining opiate antagonist administration into the medial septum produced a modest augmentation of latent inhibition. The medial septal region appears to provide a site where opiate manipulations alter some aspect of retention for events that occur in the absence of reinforcement.
研究了阿片类药物处理对家兔经典条件反射性心率的潜伏抑制作用。动物先接触一种听觉刺激，该刺激后来用作条件刺激（CS）。在CS预暴露阶段之前或之后立即向内侧隔区注射激动剂左啡诺，可减弱条件反应的潜伏抑制。在习惯化长期保持无变化的动物中观察到了这种效应。向杏仁核中央核注射左啡诺无效，杏仁核中央核是阿片类药物对厌恶条件反射任务起作用的敏感部位。对在隔区内获得的效应进行的进一步分析揭示了药理学特异性。训练后注射左啡诺的效应也具有时间依赖性，并表现出神经解剖学特异性。训练后向内侧隔区注射阿片类拮抗剂可适度增强潜伏抑制。内侧隔区似乎是一个部位，在该部位阿片类药物处理会改变对无强化事件的记忆保持的某些方面。
