Enrico P, Migliore M, Spiga S, Mulas G, Caboni F, Diana M
Department of Biomedical Sciences, University of Sassari, V.le S. Pietro 43/B, Sassari 07100, Italy.
Institute of Biophysics, National Research Council, Via U. La Malfa 153, Palermo 90146, Italy.
Neuroscience. 2016 May 13;322:195-207. doi: 10.1016/j.neuroscience.2016.02.006. Epub 2016 Feb 17.
Dopamine (DA) neurons of the ventral tegmental area (VTA) play a key role in the neurobiological basis of goal-directed behaviors and addiction. Morphine (MOR) withdrawal induces acute and long-term changes in the morphology and physiology of VTA DA cells, but the mechanisms underlying these modifications are poorly understood. Because of their predictive value, computational models are a powerful tool in neurobiological research, and are often used to gain further insights and deeper understanding on the molecular and physiological mechanisms underlying the development of various psychiatric disorders. Here we present a biophysical model of a DA VTA neuron based on 3D morphological reconstruction and electrophysiological data, showing how opiates withdrawal-driven morphological and electrophysiological changes could affect the firing rate and discharge pattern. The model findings suggest how and to what extent a change in the balance of GABA/GLU inputs can take into account the experimentally observed hypofunction of VTA DA neurons during acute and prolonged withdrawal, whereas morphological changes may play a role in the increased excitability of VTA DA cell to opiate administration observed during opiate withdrawal.
腹侧被盖区(VTA)的多巴胺(DA)神经元在目标导向行为和成瘾的神经生物学基础中起关键作用。吗啡(MOR)戒断会引起VTA DA细胞形态和生理的急性和长期变化,但这些改变背后的机制尚不清楚。由于其预测价值,计算模型是神经生物学研究中的有力工具,常用于深入了解各种精神疾病发生发展的分子和生理机制。在此,我们基于三维形态重建和电生理数据提出了一个DA VTA神经元的生物物理模型,展示了阿片类药物戒断驱动的形态和电生理变化如何影响放电频率和放电模式。模型结果表明,GABA/GLU输入平衡的变化如何以及在多大程度上能够解释急性和长期戒断期间实验观察到的VTA DA神经元功能减退,而形态变化可能在阿片类药物戒断期间观察到的VTA DA细胞对阿片类药物给药的兴奋性增加中起作用。