PLoS Biol ：多巴胺在睡眠调节中的作用

近日，西班牙研究人员发现神经递质多巴胺调节睡眠的新功能。相关研究论文发表在PLoS Biology杂志上。

多巴胺是一种神经传导物质，用来帮助细胞传送脉冲，主要负责大脑的情欲，感觉，将兴奋及开心的信息传递，也与上瘾有关。

去甲肾上腺素是一种神经递质，主要由交感节后神经元和脑内肾上腺素能神经末梢合成和分泌，是后者释放的主要递质，也是一种激素，由肾上腺髓质合成和分泌，但含量较少。循环血液中的去甲肾上腺素主要来自肾上腺髓质。

当多巴胺与其受体相互作用后，抑制去甲肾上腺素，这意味着褪黑激素的产生和释放减少。

McCormick博士解释说：这些结果是有趣的，因为多巴胺通常在刺激情况下会增加，多巴胺可直接抑制褪黑激素的产生和释放，褪黑激素主要用来引起嗜睡，诱导机体进入睡眠状态。

doi:10.1371/journal.pbio.1001347
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Circadian-Related Heteromerization of Adrenergic and Dopamine D4 Receptors Modulates Melatonin Synthesis and Release in the Pineal Gland.

González S, Moreno-Delgado D, Moreno E, Pérez-Capote K, Franco R, et al.

The role of the pineal gland is to translate the rhythmic cycles of night and day encoded by the retina into hormonal signals that are transmitted to the rest of the neuronal system in the form of serotonin and melatonin synthesis and release. Here we describe that the production of both melatonin and serotonin by the pineal gland is regulated by a circadian-related heteromerization of adrenergic and dopamine D₄ receptors. Through α_1B-D₄ and β₁-D₄ receptor heteromers dopamine inhibits adrenergic receptor signaling and blocks the synthesis of melatonin induced by adrenergic receptor ligands. This inhibition was not observed at hours of the day when D₄ was not expressed. These data provide a new perspective on dopamine function and constitute the first example of a circadian-controlled receptor heteromer. The unanticipated heteromerization between adrenergic and dopamine D₄ receptors provides a feedback mechanism for the neuronal hormone system in the form of dopamine to control circadian inputs.