Flexner J B, Flexner L B, Church A C
Pharmacol Biochem Behav. 1983 Apr;18(4):519-23. doi: 10.1016/0091-3057(83)90274-5.
Bitemporal injections of puromycin that primarily affect the hippocampal-entorhinal areas consistently cause amnesia of maze-learning in mice for 3 days after training but become consistently ineffective if given 6 or more days after training. At these later times, additional puromycin injection sites covering widespread areas of the forebrain are necessary to induce amnesia. These observations are interpreted to indicate that the locus of the engram has become more widespread within the 6-day period. Treatment with inhibitors of dopamine beta-hydroxylase for 3 days following training, retarded the spread of memory from a matter of days to a period of weeks. Repeated treatment with the inhibitors restricted engram spread for about 3 months; again spread was evident about a month after the last treatment. These observations imply that the mechanisms responsible for engram spread are capable of surviving for extraordinarily long periods of time.
双侧颞叶注射嘌呤霉素主要影响海马-内嗅区，在训练后持续导致小鼠迷宫学习失忆3天，但如果在训练后6天或更长时间给药则持续无效。在这些较晚的时间点，需要额外的嘌呤霉素注射部位覆盖前脑的广泛区域来诱导失忆。这些观察结果被解释为表明记忆痕迹在6天内变得更加广泛。训练后用多巴胺β-羟化酶抑制剂治疗3天，将记忆的扩散从几天延缓到几周。用抑制剂重复治疗可将记忆痕迹的扩散限制约3个月；最后一次治疗后约一个月再次出现扩散明显。这些观察结果表明，负责记忆痕迹扩散的机制能够存活非常长的时间。
