Departamento de Fisiología, Facultad de Medicina, Universidad de la República, Uruguay.
WebSciences International and UCLA School of Medicine, Los Angeles, USA.
Peptides. 2018 Jun;104:50-61. doi: 10.1016/j.peptides.2018.04.009. Epub 2018 Apr 20.
Neurons that utilize melanin-concentrating hormone (MCH) as a neuromodulator are localized in the postero-lateral hypothalamus and incerto-hypothalamic area. These neurons project diffusely throughout the central nervous system and have been implicated in critical physiological processes, such as sleep. Unlike rodents, in the order carnivora as well as in humans, MCH exerts its biological functions through two receptors: MCHR-1 and MCHR-2. Hence, the cat is an optimal animal to model MCHergic functions in humans. In the present study, we examined the distribution of MCH-positive fibers in the brainstem of the cat. MCHergic axons with distinctive varicosities and boutons were heterogeneously distributed, exhibiting different densities in distinct regions of the brainstem. High density of MCHergic fibers was found in the dorsal raphe nucleus, the laterodorsal tegmental nucleus, the periaqueductal gray, the pendunculopontine tegmental nucleus, the locus coeruleus and the prepositus hypoglossi. Because these areas are involved in the control of REM sleep, the present anatomical data support the role of this neuropeptidergic system in the control of this behavioral state.
利用黑色素浓缩激素 (MCH) 作为神经调质的神经元位于下丘脑后外侧和下丘脑神经核团。这些神经元在中枢神经系统中广泛投射，并与关键的生理过程有关，如睡眠。与啮齿动物不同，在食肉目动物以及人类中，MCH 通过两种受体发挥其生物学功能：MCHR-1 和 MCHR-2。因此，猫是模拟人类 MCH 能功能的理想动物。在本研究中，我们研究了猫脑干中 MCH 阳性纤维的分布。具有独特膨体和小结的 MCH 能轴突呈异质性分布，在脑干的不同区域表现出不同的密度。在中缝背核、外侧背侧脑桥核、导水管周围灰质、脚桥被盖核、蓝斑核和舌下神经前置核中发现了高密度的 MCH 能纤维。由于这些区域参与 REM 睡眠的控制，目前的解剖学数据支持这种神经肽系统在控制这种行为状态中的作用。
