Department of Physiology, Monash University, Clayton, VIC 3183, Australia.
Trends Neurosci. 2011 Jan;34(1):31-40. doi: 10.1016/j.tins.2010.10.001. Epub 2010 Oct 28.
Ghrelin is a peptide hormone produced and secreted in the stomach. Numerous studies over the past decade demonstrate its importance in food intake, body-weight regulation and glucose homeostasis. These effects are driven largely by the high expression of the ghrelin receptor (GHSR1a) in the hypothalamus. However, GHSR1a is also expressed in numerous extra-hypothalamic neuronal populations, suggesting that ghrelin has physiological functions besides those involved in metabolic functions. In this review, I focus on increasing evidence that ghrelin has important roles in extra-hypothalamic functions, including learning and memory, reward and motivation, anxiety and depression, and neuroprotection. Furthermore, I discuss how the recently demonstrated role of ghrelin in promoting survival during periods of caloric restriction could contribute to its inherent neuroprotective and neuromodulatory properties.
胃饥饿素是一种在胃中产生和分泌的肽类激素。过去十年的大量研究表明，它在摄食、体重调节和葡萄糖稳态中具有重要作用。这些作用主要是由下丘脑内胃饥饿素受体（GHSR1a）的高表达驱动的。然而，GHSR1a 也在许多下丘脑外神经元群体中表达，这表明除了与代谢功能相关的作用外，胃饥饿素还具有生理功能。在这篇综述中，我重点介绍了越来越多的证据表明，胃饥饿素在下丘脑外功能中具有重要作用，包括学习和记忆、奖励和动机、焦虑和抑郁以及神经保护。此外，我还讨论了最近发现的胃饥饿素在热量限制期间促进生存的作用如何有助于其固有的神经保护和神经调节特性。
