Neuroscience Graduate Program, University of Michigan, Ann Arbor, MI, United States; Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI, United States; Elizabeth W. Caswell Diabetes Institute, University of Michigan, Ann Arbor, MI, United States.
Elizabeth W. Caswell Diabetes Institute, University of Michigan, Ann Arbor, MI, United States.
Front Neuroendocrinol. 2023 Jul;70:101069. doi: 10.1016/j.yfrne.2023.101069. Epub 2023 May 5.
Hypothalamic melanin-concentrating hormone (MCH) neurons participate in many fundamental neuroendocrine processes. While some of their effects can be attributed to MCH itself, others appear to depend on co-released neurotransmitters. Historically, the subject of fast neurotransmitter co-release from MCH neurons has been contentious, with data to support MCH neurons releasing GABA, glutamate, both, and neither. Rather than assuming a position in that debate, this review considers the evidence for all sides and presents an alternative explanation: neurochemical identity, including classical neurotransmitter content, is subject to change. With an emphasis on the variability of experimental details, we posit that MCH neurons may release GABA and/or glutamate at different points according to environmental and contextual factors. Through the lens of the MCH system, we offer evidence that the field of neuroendocrinology would benefit from a more nuanced and dynamic interpretation of neurotransmitter identity.
下丘脑黑色素浓缩激素 (MCH) 神经元参与许多基本的神经内分泌过程。虽然它们的一些作用可以归因于 MCH 本身，但其他作用似乎取决于共释放的神经递质。从历史上看，MCH 神经元快速释放神经递质的问题一直存在争议，有数据支持 MCH 神经元释放 GABA、谷氨酸、两者兼有和两者都没有。本综述并没有在这场争论中选择立场，而是考虑了所有方面的证据，并提出了一个替代解释：神经化学特性，包括经典神经递质的含量，是可以改变的。本综述强调了实验细节的可变性，我们假设 MCH 神经元可能根据环境和上下文因素在不同时间点释放 GABA 和/或谷氨酸。通过 MCH 系统的视角，我们提供了证据表明，神经内分泌学领域将受益于对神经递质特性更细致和动态的解释。
