Wang Kun, Mao Wei, Zhang Xiaoyu, Zhao Yufei, Fan Kuikui, Pan Deng, Liu Haodong, Li Penghui, Hai Rihan, Du Chenguang
Institute of Cereal and Oil Crops, Hebei Academy of Agriculture and Forestry Sciences, Shijiazhuang 050000, China.
College of Veterinary Medicine, Inner Mongolia Agricultural University, Hohhot 010018, China.
Open Life Sci. 2020 Aug 13;15(1):580-587. doi: 10.1515/biol-2020-0063. eCollection 2020.
Melanocortin-4 receptors (MC4Rs) are key regulators of energy homeostasis and adipose deposition in the central nervous system. Considering that MC4R expression regions and function-related research mainly focus on the paraventricular nucleus (PVN), little is known about their distribution throughout the mouse brain, although its messenger RNA distribution has been analyzed in the rat. Therefore, MC4R protein localization in mouse neurons was the focus of this study.
MC4R protein distribution was assessed in mice through immunofluorescence and Western blotting.
MC4R was differentially expressed throughout the arcuate nucleus (ARC), nucleus of the solitary tract (NTS), raphe pallidus (RPa), medial cerebellar nucleus, intermediolateral nucleus, and brainstem. The highest MC4R protein levels were found in the ARC and ventromedial hypothalamic nucleus, while they were significantly lower in the parabrachial nucleus and NTS. The lowest MC4R protein levels were found in the PVN; there was no difference in the protein levels between the area postrema and RPa.
These data provide a basic characterization of MC4R-expressing neurons and protein distribution in the mouse brain and may aid further research on its role in energy homeostasis.
黑皮质素-4受体（MC4Rs）是中枢神经系统中能量稳态和脂肪沉积的关键调节因子。鉴于MC4R表达区域及功能相关研究主要集中在室旁核（PVN），尽管已对大鼠的信使核糖核酸分布进行了分析，但对于其在小鼠全脑的分布情况却知之甚少。因此，本研究聚焦于小鼠神经元中MC4R蛋白的定位。
通过免疫荧光和蛋白质印迹法评估小鼠体内MC4R蛋白的分布。
MC4R在整个弓状核（ARC）、孤束核（NTS）、中缝苍白核（RPa）、小脑内侧核、中间外侧核及脑干中呈差异表达。在ARC和下丘脑腹内侧核中发现MC4R蛋白水平最高，而在臂旁核和NTS中则显著较低。在PVN中发现MC4R蛋白水平最低；最后区和RPa之间的蛋白水平无差异。
这些数据提供了小鼠脑中表达MC4R的神经元及其蛋白分布的基本特征，可能有助于进一步研究其在能量稳态中的作用。
