Analysis of memory formation and readout in the slug

蛞蝓具有气味-味觉联想学习功能，本研究旨在从生理学和分子生物学的角度阐明蛞蝓气味学习的机制。一个高频刺激的唇神经，这是一个在体外模拟的非条件刺激，引起的频率增加，在当地的Meld电位振荡在prorebrum（PC），以及兴奋的爆发PC神经元和抑制的nonbursting PC神经元。由于非爆发神经元被认为是PC的主要神经元，并可能介导从PC到其他脑区的信息输出，这些结果表明，在条件反射过程中，PC的信息输出减少。高频刺激腱神经可使PC诱发电位增强，持续时间超过2 h。这种可塑性的变化，在PC的突触传递的功效可能参与气味learning.Injection的蛋白质合成抑制剂茴香霉素或放线菌酮受损的记忆保留后2-7天改变条件反射，表明蛋白质合成是必要的长期记忆的保留。我们进一步探索基因诱导的气味-味觉关联条件反射使用PCR-差异显示方法在大脑中的配对和非配对的条件动物。用100对随机引物扩增出12个条带，并克隆了8个基因的部分序列。

Slugs perform odor-taste associative learning, and the present work was aimed at clarifying the mechanisms of odor learning using physiological and molecular biological methods. A high frequency stimulation of the lip nerve, which is an in vitro analog of the unconditioned stimulus, caused an increased frequency in the local Meld potential oscillation in the procerebrum (PC), as well as excitation of the bursting PC neurons and inhibition of the nonbursting PC neurons. As the nonbursting neurons are thought to be the principal neurons of the PC and may mediate output of information from the PC to other brain regions, these results suggest that output of information from the PC is decreased during conditioning. A high frequency stimulation of the tentacle nerve resulted in a potentiation of the evoked potential in the PC, which lasted for more than 2 h. Such plastic changes in the efficacy of synaptic transmission in the PC may be involved in odor learning.Injection of the protein synthesis inhibitors anisomycin or cycloheximide impaired memory retention after 2-7 days alter conditioning, indicating that protein synthesis is necessary for the retention of long-term memory. We further explored genes induced by the odor-taste associative conditioning using the PCR-differential display method in the brains from paired and unpaired conditioned animals. Using 100 pairs of random primers, 12 bands showed a reproducible induction pattern, and partial sequences of 8 genes were cloned.