Bures J, Buresova O, Ivanova S F
Institute of Physiology, Czechoslovak Academy of Sciences, Prague.
Arch Int Physiol Biochim Biophys. 1991 Sep;99(5):A131-4.
Acquisition of conditioned taste aversion (CTA) in rats is not prevented by functional decortication, anesthesia or hypothermia applied after intake of the flavored fluid and maintained throughout the action of the poison but is disrupted by bilateral application of 10 ng tetrodotoxin (TTX) into the parabrachial nuclei. The blockade is directly proportional to TTX dosage, indirectly proportional to distance of the injection site from parabrachial nuclei and equally affects CTAs using different CS (saccharin, NaCl) and different US (LiCl, carbachol, amphetamine, cycloheximide). CTA is disrupted by TTX applied up to 4 but not 8 days after a single CS-US pairing. TTX fails to disrupt overtrained CTA and elicits only a weak anterograde amnesia when applied 1 but 2 or more days before CTA acquisition. It is concluded that the parabrachial nuclei and the adjacent reticular formation probably represent the neural substrate of the permanent CTA engram the protracted consolidation of which is disrupted by prolonged cessation of impulse which is disrupted by prolonged cessation of impulse activity in the information storing network.
大鼠条件性味觉厌恶（CTA）的形成，在摄入调味液后施加功能性去皮质、麻醉或体温过低并在毒物作用全程维持的情况下不会受到阻止，但向臂旁核双侧注射10纳克河豚毒素（TTX）会破坏CTA的形成。这种阻断作用与TTX剂量成正比，与注射部位距臂旁核的距离成反比，并且对使用不同条件刺激（糖精、氯化钠）和不同非条件刺激（氯化锂、卡巴胆碱、苯丙胺、环己酰亚胺）的CTA均有同等影响。在单次条件刺激 - 非条件刺激配对后4天内施加TTX会破坏CTA，但8天后则不会。TTX不会破坏过度训练的CTA，并且在CTA形成前1天施加时只会引发微弱的顺行性遗忘，但在2天或更长时间前施加时则不会。得出的结论是，臂旁核和相邻的网状结构可能代表了永久性CTA记忆痕迹的神经基础，其长期巩固过程会因信息存储网络中冲动活动的长期停止而受到破坏。
