Johnstone Louise E, Fong Tung M, Leng Gareth
Centre for Integrative Physiology, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh EH8 9XD, United Kingdom.
Cell Metab. 2006 Oct;4(4):313-21. doi: 10.1016/j.cmet.2006.08.003.
We trained rats to a regime of scheduled feeding, in which food was available for only 2 hr each day. After 10 days, rats were euthanized at defined times relative to food availability, and their brains were analyzed to map Fos expression in neuronal populations to test the hypothesis that some populations are activated by hunger whereas others are activated by satiety signals. Fos expression accompanied feeding in several hypothalamic and brainstem nuclei. Food ingestion was critical for Fos expression in noradrenergic and non-noradrenergic cells in the nucleus tractus solitarii and area postrema and in the supraoptic nucleus, as well as in melanocortin-containing cells of the arcuate nucleus. However, anticipation of food alone activated other neurons in the arcuate nucleus and in the lateral and ventromedial hypothalamus, including orexin neurons. Thus orexigenic populations are strongly and rapidly activated at the onset of food presentation, followed rapidly by activity in anorexigenic populations when food is ingested.
我们训练大鼠按照定时喂食模式进食，即每天仅在2小时内提供食物。10天后，在与食物供应相关的特定时间对大鼠实施安乐死，并对其大脑进行分析，以绘制神经元群体中的Fos表达图谱，从而检验某些群体被饥饿激活而其他群体被饱腹感信号激活这一假设。在几个下丘脑和脑干核团中，Fos表达伴随着进食过程。食物摄入对于孤束核、最后区、视上核中去甲肾上腺素能和非去甲肾上腺素能细胞以及弓状核中含黑皮质素的细胞中的Fos表达至关重要。然而，仅对食物的预期就激活了弓状核以及下丘脑外侧和腹内侧的其他神经元，包括食欲素神经元。因此，在食物呈现开始时，促食欲群体被强烈且迅速地激活，随后在摄入食物时，厌食群体迅速活跃起来。
