School of Medical Instrument and Food Engineering, University of Shanghai for Science and Technology, 516 Jun Gong Road, Shanghai 200093, China.
Brain Res Bull. 2012 Apr 10;87(6):556-63. doi: 10.1016/j.brainresbull.2012.01.011. Epub 2012 Feb 6.
The prefrontal cortex has been extensively implicated in autism to explain deficits in executive and other higher brain functions related to cognition, language, sociability and emotion. Hyper-connectivity and hyper-plasticity at the level of the neuronal microcircuit in the medial prefrontal cortex (mPFC) in the valproic acid (VPA) animal model of autism has been suggested. However, the possible alterations at the system levels are not well understood. The present study investigated the basal synaptic transmission and synaptic plasticity in the mPFC in vivo in the VPA rat model of autism. Furthermore, short-term and long-term retention of fear memories were also examined. The findings displayed that paired-pulse facilitation (PPF) and long-term potentiation (LTP), representing short- and long-term synaptic plasticity, were enhanced by the prenatal exposure to VPA. In addition, the short- and long-term fear memories were enhanced. These results suggest that enhanced synaptic plasticity in the mPFC and fear memories might be one of the mechanisms underlying some symptoms of autism.
前额皮质在自闭症中被广泛涉及，以解释与认知、语言、社交和情绪相关的执行功能和其他更高脑功能的缺陷。在自闭症的丙戊酸（VPA）动物模型中，内侧前额皮质（mPFC）的神经元微电路水平上存在超连接和超可塑性。然而，系统水平上的可能改变还不是很清楚。本研究在自闭症的 VPA 大鼠模型中体内研究了 mPFC 的基础突触传递和突触可塑性。此外，还检查了短期和长期恐惧记忆的保留情况。研究结果显示，由产前暴露于 VPA 引起的成对脉冲易化（PPF）和长时程增强（LTP），分别代表短期和长期突触可塑性增强。此外，短期和长期恐惧记忆也增强了。这些结果表明，mPFC 中的增强的突触可塑性和恐惧记忆可能是自闭症的一些症状的机制之一。
