Loskutova L V
Institute of Physiology, Siberian Division, Academy of Medical Sciences, USSR.
Neurosci Behav Physiol. 1990 Nov-Dec;20(6):500-5. doi: 10.1007/BF01237275.
The activity of serotoninergic neurons of the medial raphé nucleus was turned off by local injection of the neurotoxin, 5,7-dihydroxytryptamine. Seven days later, a conditioned passive avoidance reaction was developed following 20 preexposures to the conditional stimulus (the presentation of the experimental chamber). As compared with the sham-operated control, in which 20 preexposures to the stimulus elicited latent inhibition, i.e., attenuation of the reproduction of the conditioned passive avoidance reaction, prolonged maintenance at the formed level, and lack of susceptibility to amnesia, all of the enumerated features were disturbed in animals administered the neurotoxin. The administration of haloperidol (0.5 mg/kg) 1 h prior to training reestablished the state of latent inhibition which had been disrupted by the switching off of the mesolimbic serotonin system. It is hypothesized that the process of the suppression of attention to the nonreinforced signals during the preexposure to the stimulus is achieved by the interaction of the serotoninergic and dopaminergic systems.
通过向中缝核局部注射神经毒素5,7-二羟基色胺，可使中缝核中5-羟色胺能神经元的活动停止。7天后，在对条件刺激（实验箱的呈现）进行20次预暴露后，形成了条件性被动回避反应。与假手术对照组相比，在假手术对照组中，对刺激进行20次预暴露会引发潜伏抑制，即条件性被动回避反应的再现减弱、在形成的水平上维持时间延长以及对遗忘不敏感，而在给予神经毒素的动物中，所有这些特征均受到干扰。在训练前1小时给予氟哌啶醇（0.5毫克/千克）可重新建立因中脑边缘5-羟色胺系统关闭而被破坏的潜伏抑制状态。据推测，在对刺激进行预暴露期间，对未强化信号的注意力抑制过程是通过5-羟色胺能系统和多巴胺能系统的相互作用实现的。
