The Role of Cholinergic Neuron System in the Plasticity of Developing Somatosensory Cortex, 2005

1.先前的研究表明，小鼠基底前脑胆碱能投射的新生儿电解损伤导致新皮质胆碱能短暂耗竭，并导致皮质细胞结构和认知能力的永久性改变。我们研究了新生儿基底前脑病变是否会改变新皮质的可塑性。利用细胞色素氧化酶组织化学，我们发现基底前脑损伤动物的可塑性指数降低。我们的数据表明，胆碱能输入在调节小鼠感觉-运动皮层的可塑性和形态发生中发挥作用。为了研究瞬时表达的5 -羟色胺转运体在丘脑皮质轴突中的作用，我们给怀孕的大鼠和幼崽服用了帕罗西汀和SSRI。我们发现，帕罗西汀治疗的动物皮质5-HT和5-HIAA水平显著下降。此外，我们发现在帕罗西汀治疗组中，斑块和间隔的面积显着减少。在帕罗西汀治疗的小鼠中，翻正反射的建立出现延迟。我们的数据可能表明，围产期5-羟色胺再摄取到丘脑皮质纤维可能在形态学和神经元功能上促进大鼠桶状皮质的发育。

1.Previous studies have shown that neonatal electrolytic lesions of basal forebrain cholinergic projections in mice lead to a transient cholinergic depletion of neocortex and to permanent alterations in cortical cytoarchitecture and cognitive performance. We examined whether neonatal lesions of the basal forebrain modify neocortical plasticity. Using cytochrome oxidase histochemistry, we have shown that an index of plasticity was reduced in the basal forebrain lesioned animals. Our data suggest that cholinergic inputs play a role in regulating plasticity as well as in the morphogenesis of mouse sensory-motor cortex.2.To investigate the role of the transiently expressed serotonin transporter in the thalamocortical axons, paroxetine, an SSRI was administered to pregnant rats and pups. We have found that paroxetine-treated animals revealed a significant decrease in the level of cortical 5-HT and 5-HIAA. Also, we have found that the areas of patches and septa were significantly decreased in the paroxetine-treated groups. A delay of establishment in righting reflex was seen in paroxetine-treated mice. Our data might suggest that 5-HT reuptake into thalamocortical fibers perinatally might contribute to the rat barrel cortex development both in morphology and in neuronal function.