Significance of dopamine transmission in the rat medial prefrontal cortex for conditioned fear.
Significance of dopamine transmission in the rat medial prefrontal cortex for conditioned fear.
复制标题
大鼠内侧前额叶皮层多巴胺传递对条件性恐惧的意义。
作者：
M. Pezze;T. Bast;J. Feldon,
先前的研究表明，条件性恐惧刺激会激活内侧前额皮质（mPFC）中的多巴胺传递。因此，本研究调查了 mPFC 多巴胺对于对音调的条件性恐惧反应的功能意义。我们在 Wistar 大鼠的经典恐惧调节范例中，分别通过局部微量输注 D1/D2 受体拮抗剂顺式氟哌噻吨或间接多巴胺受体激动剂 D-安非他明来检查抑制或刺激 mPFC 多巴胺传递的效果。老鼠接受音调电击配对，然后单独接触音调。冻结被用来衡量条件性恐惧。在音调-电击配对期间，mPFC 中药物的存在不会影响随后单独呈现音调时的冻结。然而，当在单独呈现音调期间顺式氟哌噻吨和 D-安非他明存在于 mPFC 中时，音调的冻结会减少。我们证明，冻结减少既不能用状态依赖性解释，也不能用输注引起的活动改变来解释。我们的数据表明，mPFC 多巴胺传递对于条件性恐惧的检索/表达很重要，但不是形成。通过前额输注顺式氟哌噻吨和 D-安非他明减少条件性恐惧可能反映了条件性恐惧的正常表达需要 mPFC 多巴胺活性的最佳水平。
Previous studies have demonstrated activation of dopamine transmission in the medial prefrontal cortex (mPFC) by conditioned fear stimuli. Therefore, the present study investigated the functional significance of mPFC dopamine for a conditioned fear response to a tone. We examined the effects of inhibition or stimulation of mPFC dopamine transmission by local microinfusion of the D1/D2-receptor antagonist cis-flupenthixol or the indirect dopamine receptor agonist D-amphetamine, respectively, in a classical fear-conditioning paradigm in Wistar rats. Rats received tone-shock pairings and were later exposed to the tone alone. Freezing was used as measure of conditioned fear. Presence of the drugs in the mPFC during the tone-shock pairings did not affect freezing during subsequent presentation of the tone alone. However, when cis-flupenthixol and D-amphetamine were present in the mPFC during presentation of the tone alone, freezing to the tone was reduced. We demonstrated that the decreased freezing could be explained neither by state dependency nor infusion-induced alterations in activity. Our data indicate that mPFC dopamine transmission is important for the retrieval/expression, but not the formation, of conditioned fear. The reduction of conditioned fear by prefrontal infusion of both cis-flupenthixol and D-amphetamine may reflect normal expression of conditioned fear requires an optimal level of mPFC dopamine activity.
大鼠脑组织中阿朴啡对映体的受体亲和力。
影响因子：
5
作者：
Baldessarini,RJ;Kula,NS;Zong,R;Neumeyer,JL
通讯作者：
Neumeyer,JL
影响因子：
3.7
作者：
Bechara, A;Damasio, H;Damasio, AR
通讯作者：
Damasio, AR
影响因子：
1.9
作者：
Gewirtz, JC;Falls, WA;Davis, M
通讯作者：
Davis, M