Ferry B, Sandner G, Di Scala G
L.N.C.C., URA 1939 C.N.R.S., Strasbourg, France.
Neurobiol Learn Mem. 1995 Sep;64(2):169-80. doi: 10.1006/nlme.1995.1056.
The present study aimed at documenting the neurobiological substrate of taste-potentiated odor aversion (TPOA) in the rat. The role of several temporal lobe structures in discriminative TPOA learning was questioned. The effects of excitotoxic lesions (ibotenate) of the basolateral amygdaloid nucleus, the central amygdaloid nucleus, the caudate putamen nucleus, and aspirative lesion of the entorhinal cortex were studied. The results show that only basolateral amygdaloid nucleus (ABL) damage impaired TPOA. This effect was selective of TPOA, since it spared conditioned taste aversion (CTA) and olfactory perception. In order to find out which process in TPOA requires normal functioning of the ABL, the effects of microinjections of a GABAA agonist (muscimol) into the ABL at various stages of the experiment were examined. The results show that application of muscimol during the acquisition, before or after the presentation of the odor-taste stimulus, impaired TPOA without affecting CTA. Contrastingly, application of muscimol before the test impaired neither TPOA nor CTA. These results suggest that ABL is involved in the acquisition but not in the retrieval of TPOA. The efficacy of muscimol microinjected after the presentation of the odor-taste stimulus further suggests that the deficit is not due to a sensory impairment but rather to the disruption of a memory process, critical for TPOA.
本研究旨在记录大鼠味觉增强性气味厌恶（TPOA）的神经生物学基础。人们对几个颞叶结构在辨别性TPOA学习中的作用提出了质疑。研究了基底外侧杏仁核、中央杏仁核、尾状壳核的兴奋性毒性损伤（异搏亭）以及内嗅皮质的抽吸损伤的影响。结果表明，只有基底外侧杏仁核（ABL）损伤会损害TPOA。这种效应是TPOA特有的，因为它不影响条件性味觉厌恶（CTA）和嗅觉感知。为了找出TPOA中的哪个过程需要ABL的正常功能，研究了在实验的各个阶段向ABL微量注射GABAA激动剂（蝇蕈醇）的影响。结果表明，在气味-味觉刺激呈现之前或之后的习得过程中应用蝇蕈醇会损害TPOA，但不影响CTA。相反，在测试前应用蝇蕈醇既不损害TPOA也不损害CTA。这些结果表明，ABL参与TPOA的习得，但不参与其提取。在气味-味觉刺激呈现后微量注射蝇蕈醇的效果进一步表明，缺陷不是由于感觉障碍，而是由于对TPOA至关重要的记忆过程的破坏。
