Intrapallidal D2 dopamine receptors control globus pallidus neuron activity in the rat
Intrapallidal D2 dopamine receptors control globus pallidus neuron activity in the rat
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DOI：
10.1016/s0304-3940(01)01550-6
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发表时间：
2001-03
影响因子：
2.5
通讯作者：
E. Querejeta;A. Delgado;R. Valdiosera;D. Erlij;J. Aceves
中科院分区：
文献类型：
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作者：
E. Querejeta;A. Delgado;R. Valdiosera;D. Erlij;J. Aceves
由于 D2 多巴胺受体的激活会抑制苍白球内神经末梢释放 γ-氨基丁酸 (GABA)，因此我们测量了多巴胺 D2 受体修饰剂对麻醉大鼠苍白球 (GP) 单个神经元放电率的影响。苍白球内注射选择性 D2 激动剂喹吡罗的主要作用是增加自发放电率，而 D2 阻滞剂舒必利导致自发放电率下降。 GP 神经元的自发放电受到刺激 GABA 能纹状体苍白球投射的抑制。因此，我们测量了 D2 受体修饰剂对 GP 神经元纹状体抑制的影响，发现苍白球内喹吡罗阻断了纹状体刺激的抑制作用，而舒必利增强了纹状体刺激的抑制作用。这些实验表明，苍白球神经元的自发放电率及其通过纹状体苍白球输入的修饰均由苍白球内多巴胺 D2 受体控制。此外，结合文献中的其他发现，我们的结果表明，苍白球内多巴胺 D2 受体的激活会抑制突触前末梢的 GABA 释放。
Because activation of D2dopamine receptors inhibits γ-aminobutyric acid (GABA) release from intrapallidal nerve terminals, we measured the effects of modifiers of dopamine D2receptors on the firing rate of single neurons in the globus pallidus (GP) of the anesthetized rat. The predominant effect of intrapallidal administration of the selective D2agonist quinpirole was an increase in the rate of spontaneous firing while the D2blocker sulpiride caused a decrease. The spontaneous firing of GP neurons is inhibited by stimulation of the GABAergic striatopallidal projection. We therefore measured the effects of modifiers of D2receptors on striatal inhibition of GP neurons and found that intrapallidal quinpirole blocked the inhibitory effects of striatal stimulation while sulpiride enhanced them. These experiments show that both the spontaneous rate of firing of pallidal neurons and its modification by striatopallidal inputs is controlled by intrapallidal dopamine D2receptors. In addition, taken together with other findings in the literature, our results suggest that activation of dopamine D2receptors within the globus pallidus leads to inhibition of GABA release from presynaptic terminals.