Neuromedin U suppresses prolactin secretion via dopamine neurons of the arcuate nucleus.
Neuromedin U suppresses prolactin secretion via dopamine neurons of the arcuate nucleus.
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Neuromedin U 通过弓状核的多巴胺神经元抑制催乳素分泌。
DOI：
10.1016/j.bbrc.2019.10.156
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发表时间：
2020
期刊：
影响因子：
--
通讯作者：
and Murakami N
中科院分区：
文献类型：
--
作者：
2.Nakahara K;Maruyama K;Ensho T;Mori K;Miyazato M;Kangawa K;Uemura R;Sakota H;Nakazato M;and Murakami N
神经介肽U（NMU）具有含有一个由33或36个氨基酸残基组成的额外肽的前体。最近，我们从大鼠脑中鉴定出第二种肽，并将其命名为神经介肽受体相关肽（neuromedin U receptor-related peptide，NVP），表明当通过脑室内（icv）途径注射时，NVP可刺激垂体催乳素释放。在这里，我们研究是否NMU，像CNOMP，也刺激催乳素的释放。脑室内注射NMU可显著降低垂体催乳素的分泌，与NMU的作用不同。NMU对催乳素释放的这种抑制作用在泌乳、应激、假孕、多潘立酮（多巴胺拮抗剂）给药和icv注射CVP等高催乳素状态下观察到。免疫组织化学分析显示，icv注射NMU诱导cFos表达的多巴胺能神经元的弓状核，但不是黑质。NMU和神经介肽S（NMS）双敲除的小鼠（后者也与NMU受体结合）显示，相对于野生型小鼠，多潘立酮治疗后血浆催乳素水平显著增加。这些结果表明，NMU和CNOP可能在生理催乳素分泌中发挥重要的相互作用。
Neuromedin U (NMU) has a precursor that contains one additional peptide consisting of 33 or 36 amino acid residues. Recently, we identified this second peptide from rat brain and designated it neuromedin U precursor-related peptide (NURP), showing it to stimulate prolactin release from the pituitary when injected via the intracerebroventricular (icv) route. Here, we examined whether NMU, like NURP, also stimulates prolactin release. Unlike NURP, icv injection of NMU significantly decreased the secretion of prolactin from the pituitary. This suppression of prolactin release by NMU was observed in hyper-prolactin states such as lactation, stress, pseudopregnancy, domperidone (dopamine antagonist) administration, and icv injection of NURP. Immunohistochemical analysis revealed that icv injection of NMU induced cFos expression in dopaminergic neurons of the arcuate nucleus, but not the substantia nigra. Mice with double knockout of NMU and neuromedin S (NMS), the latter also binding to NMU receptors, showed a significant increase of the plasma prolactin level after domperidone treatment relative to wild-type mice. These results suggest that NMU and NURP may play important reciprocal roles in physiological prolactin secretion.