Stefani A, Pisani A, Bernardi G, Bonci A, Mercuri N B, Stratta F, Calabresi P
Clinica Neurologica, Università di Roma Tor Vergata, Italy.
J Neural Transm Suppl. 1995;45:61-6.
In the last decades, the contribution given by basic electrophysiology to the understanding of the nigrostriatal pathway in mammals has been rather important. The main results obtained by our group will be revised in this short review. The most common responses produced by dopamine (DA) on the principal striatal cells (the medium spiny neurons) are the modulation of the corticostriatal synaptic transmission and the decrease of voltage-dependent inward conductances. After blockade of DA transmission, both spontaneous and cortically driven glutamatergic postsynaptic potentials were inhibited by the selective activation of DA D2 receptors. In naive animals, the DA-mediated inhibition of postsynaptic firing activity was mediated by D1 receptor activation. Nevertheless, the two main subclasses of DA receptors seemed to cooperate in the formation of the long-term depression (LTD) of excitatory synaptic transmission in the striatum. The excitotoxic hypothesis of neurodegeneration has further stimulated our interest towards the study of the interactions between DA and other neurotransmitters into the basal ganglia.
在过去几十年中，基础电生理学对理解哺乳动物黑质纹状体通路所做的贡献颇为重要。本简短综述将对我们团队取得的主要成果进行回顾。多巴胺（DA）对主要纹状体细胞（中等棘状神经元）产生的最常见反应是对皮质纹状体突触传递的调节以及电压依赖性内向电导的降低。在阻断DA传递后，DA D2受体的选择性激活抑制了自发的和皮质驱动的谷氨酸能突触后电位。在未接触过药物的动物中，DA介导的对突触后放电活动的抑制是由D1受体激活介导的。然而，DA受体的两个主要亚类似乎在纹状体兴奋性突触传递的长时程抑制（LTD）形成中相互协作。神经退行性变的兴奋性毒性假说进一步激发了我们对研究DA与基底神经节中其他神经递质之间相互作用的兴趣。
