Neurotensin (NTS) is a neuropeptide acting as a neuromodulator in the brain and is a very potent hypothermic agent. However, the cellular mechanisms of actions are not fully understood. Here we report that NTS increases the firing rate of preoptic GABAergic neurons by activating both neurotensin receptor 1 (NTSR1) and neurotensin receptor 2 (NTSR2), expressed by neurons and astrocytes, respectively. Downstream of NTSR1 the neuropeptide activated an inward current, calcium release from intracellular stores and, postsynaptically, increased frequency and amplitude of inhibitory synaptic events. NTSR2 activation in astrocytes resulted in increased excitatory input in preoptic GABAergic neurons, an effect which was dependent upon the activation of P2X4 receptors. We also found that neuromedin N acted as a selective agonist at the NTSR1. Surprisingly, activation of both NTSR1 and NTSR2 in the median preoptic nucleus was required for activating a full hypothermic response.

中文翻译：

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神经降压素通过激活正视前核中的神经元神经降压素受体1和星形细胞神经降压素受体2来诱导体温过低。

神经降压素（NTS）是一种神经肽，在大脑中起神经调节剂的作用，是一种非常有效的低温药物。但是，尚未完全了解细胞的作用机制。在这里，我们报道NTS通过激活分别由神经元和星形胶质细胞表达的神经降压素受体1（NTSR1）和神经降压素受体2（NTSR2）来增加视前GABA能神经元的放电速率。在NTSR1下游，神经肽激活了内向电流，钙从细胞内存储中释放，并且突触后增加了抑制性突触事件的频率和幅度。星形胶质细胞中的NTSR2激活导致视前GABA能神经元的兴奋性输入增加，该作用取决于P2X4受体的激活。我们还发现神经调节素N在NTSR1上起选择性激动剂的作用。出奇，