Sakai N, Yamamoto T
Department of Behavioral Physiology, Faculty of Human Sciences, Osaka University, Japan.
Behav Brain Res. 1998 Jun;93(1-2):63-70. doi: 10.1016/s0166-4328(97)00133-2.
When ingestion of a taste stimulus is paired with internal malaise, the animal remembers the taste and rejects its ingestion thereafter. This learning is referred to as conditioned taste aversion (CTA). To establish CTA in adult male Wistar rats, 0.1% saccharin and an i.p. injection of 0.15 M LiCl were used as the conditioned and unconditioned stimuli, respectively. To elucidate the functional role of the medial part of the parabrachial nucleus (PBmed) which receives taste information and the lateral part (PBlat) which receives general visceral information, confined electrolytic lesions were made to either of these regions. Rats with bilateral lesions of the PBlat impaired the acquisition of CTA, but those lesions made after the acquisition of CTA had no effect on the retention of this learning. The bilateral lesions of the PBmed abolished the acquisition and retention of CTA. The PBlat-lesioned rats showed normal taste preference behavior, but PBmed-lesioned rats showed impaired sensibility to taste stimuli. These results suggest that both the PBlat and PBmed are essential for the acquisition of taste aversion learning, but the PBlat is not necessary for retrieval of CTA.
当味觉刺激的摄入与体内不适同时出现时，动物会记住这种味道，并在之后拒绝摄入。这种学习被称为条件性味觉厌恶（CTA）。为了在成年雄性Wistar大鼠中建立CTA，分别使用0.1%的糖精和腹腔注射0.15 M的LiCl作为条件刺激和非条件刺激。为了阐明接受味觉信息的臂旁核内侧部分（PBmed）和接受一般内脏信息的外侧部分（PBlat）的功能作用，对这两个区域中的任何一个进行了局限性电解损伤。双侧PBlat损伤的大鼠损害了CTA的获得，但在获得CTA后进行的那些损伤对这种学习的保留没有影响。PBmed的双侧损伤消除了CTA的获得和保留。PBlat损伤的大鼠表现出正常的味觉偏好行为，但PBmed损伤的大鼠对味觉刺激的敏感性受损。这些结果表明，PBlat和PBmed对于味觉厌恶学习的获得都是必不可少的，但PBlat对于CTA的检索不是必需的。
