González-Franco Diego A, Ramírez-Amaya Víctor, Joseph-Bravo Patricia, Prado-Alcalá Roberto A, Quirarte Gina L
Departamento de Neurobiología Conductual y Cognitiva, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Campus Juriquilla, Querétaro, Querétaro 76230, Mexico.
Maestría en Nutrición Humana y Maestría en Ciencias en Neurometabolismo, Facultad de Ciencias Naturales y Facultad de Medicina, Universidad Autónoma de Querétaro, Mexico.
Neurobiol Learn Mem. 2017 Apr;140:17-26. doi: 10.1016/j.nlm.2017.02.001. Epub 2017 Feb 6.
Intense training refers to training mediated by emotionally arousing experiences, such as aversive conditioning motivated by relatively high intensities of foot-shock, which produces a strong memory that is highly resistant to extinction. Intense training protects memory consolidation against the amnestic effects of a wide variety of treatments, administered systemically or directly into brain structures. The mechanisms of this protective effect are unknown. To determine a potential neurobiological correlate of the protective effect of intense training, rats were trained in a one-trial step-through inhibitory avoidance task using different intensities of foot-shock (0.0, 0.5, 1.0, and 2.0mA). Some rats from each group were sacrificed 45min after training for immunohistochemical Arc protein detection in dorsal and ventral striatum; other rats were tested for extinction during six consecutive days, starting 48h after training. The results showed that training with 1.0 and 2.0mA produced optimal retention scores, which were significantly higher than those of the 0.5 and 0.0mA groups. Also, a higher resistance to extinction was obtained with 2.0mA than with the other intensities. A high number of neurons expressed Arc in ventral, but not in dorsal striatum in both the 1.0 and 2.0mA groups, with a larger area of Arc signal in the latter group. We conclude that an increased Arc expression may be related to enhanced synaptic plasticity in the ventral striatum, suggesting that it may be one of the physiological substrates of enhanced learning.
高强度训练是指由引发情绪的经历介导的训练，比如由相对高强度的足部电击激发的厌恶条件反射，这种训练会产生一种对消退具有高度抗性的强烈记忆。高强度训练能保护记忆巩固，使其免受全身给药或直接注入脑结构的多种治疗的遗忘效应影响。这种保护作用的机制尚不清楚。为了确定高强度训练保护作用的潜在神经生物学关联，使用不同强度的足部电击（0.0、0.5、1.0和2.0毫安），让大鼠在单次步通抑制性回避任务中接受训练。每组中的一些大鼠在训练后45分钟被处死，用于检测背侧和腹侧纹状体中的免疫组化Arc蛋白；其他大鼠在训练后48小时开始，连续六天进行消退测试。结果表明，1.0毫安和2.0毫安的训练产生了最佳的记忆保持分数，显著高于0.5毫安和0.0毫安组。此外，2.0毫安组比其他强度组表现出更高的抗消退能力。在1.0毫安和2.0毫安组中，腹侧纹状体中有大量神经元表达Arc，而背侧纹状体中没有，且后一组的Arc信号面积更大。我们得出结论，Arc表达增加可能与腹侧纹状体中增强的突触可塑性有关，这表明它可能是学习增强的生理基础之一。
